Rick Shory

Offering a little something you might not otherwise have

purple grapes hanging from the vines that are on support wires


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Growing grapes, part 2, training

Cultivated grapes are derived from wild grapes that are forest vines. This is important in understanding how to work with grape plants, to give them what they need, so they will give you what you want.

man in forest by tall tree, holding wild grapevine to show its extent up the tree

Wild grape vines grow up forest trees

In nature, grapes vines stretch from the forest floor, all the way up to the top of tall trees. Fruit grows only in the parts that reach bright sunlight. The whole point of vineyards is to give the grape plants the sun they need, while setting fruit at heights more convenient to us.

view looking upward along a wild grape vine, showing it reaching up to the top of a forest tree

Grape vine, like a rope, to the top of a tree

If we could levitate, we might have developed viticulture as a multi-story crop system, with the grapevines growing up through nut trees. We would float around in the treetops at harvest time, gathering the grapes. Once, when I was a teenager in Alabama, I climbed to the top of a tall oak, and picked three pounds of wild muscadine (Vitis rotundifolia) fruit. It was fun, but there’s no way treetop grapes would ever be practical.

At the other extreme, grape vines would grow perfectly fine, let to spread out across open ground. In parts of the desert Southwest, wild grapes scramble over rockpiles, with their roots near springs for moisture. Grape plants would be happy covering a field, but think how hard it would be to pick the fruit, stumbling through those tangled vines.

So grape growing is basically a matter of giving the plants the sun they need, while training them so we can get the fruit. Commercial method are optimized for things like long rows, so machinery can go between, and efficient use of support material. When you look at grape literature, this is what you will see, with lots of details on how to do it. The two ingredients are: Sunshine for the plants. Access for us.

Actually, there is a third factor, critters who want to eat your grapes. I’ll talk about that now, because if you get it right you’ll avoid trouble years down the line.

grape vines by wood fence, extending to support wires above the fence

Grape vines by fence, on support wires

When I lived in Colorado, I grew grape vines with the stems fanning out up one side of a wooden fence. From the top of the fence, I had support lines spanning to the end rafters on the south side of my house. I trained the vines along these sloping wires. When the plants filled in, they cast a welcome summer shade. The clusters of grapes hung down from this living roof, both picturesque and easy to harvest.

purple grapes hanging from the vines that are on support wires

Grapes in the shade canopy

I got away with it for two years. Then the raccoons found it. There was no way to keep them off. They could climb the fence any number of places, and walk along the top to get to the grapes. At first I thought they would eat only the fruit near the fence. But they kept at it, clambering out into the canopy, night after night, till finally they had eaten every grape. At least what they didn’t knock down or ruin.

Basically, I had not thought ahead to make my grapes “defensible”. After years of growing the vines, there was nothing I could do but start over. It happened that I moved to Portland, Oregon, starting over anyway; but now I carefully think about grape supports to prevent problems.

By far the biggest critter problem for home grape growing is raccoons.

Bees and wasps come to the ripe fruit, to get the juice, especially after grape skins are broken by other creatures. But these small fliers are usually minor. If you walk around barefoot, watch that you don’t step on these stinging insects, who scavenge fallen grapes.

Birds peck ripe grapes, but for me their damage has always been minor. Occasionally they may knock down a whole cluster of grapes, while taking only a few.

You might think squirrels would ravage grapes, but I have not found this to be so. A friend loaned me a book on squirrel control. The book made the important point that individual squirrels vary greatly in what they prefer to eat. Or even what they know to eat. For example, I have grown winter squash for many years. I would leave the squashes out late in the autumn, and never had any squirrel problems.  Then, one fall, I came home after a weekend away to find half a dozen squashes gnawed open, evidently for the seeds. Immediate harvest of the rest! By the next year, the squirrel who was wise to the ways of squash had evidently died or moved on, and I never had any more squirrel damage.

So it’s always possible a squirrel may arrive in your yard who is mad for grapes. When people see what I do to prevent raccoon attacks, they always think it’s for squirrels. Maybe it’s because squirrels are obvious, and active during the day, and people see them. Raccoons are secretive, and largely nocturnal.

Raccoons are abundant in nearly every urban center in North America. I have heard they are now in Europe as well. I’ve watched them go in and out of storm sewers. They travel through these underground pipes, so they can easily move through neighborhoods without being seen, and without having to cross roads above ground.

grape vines that raccoons have fed on, showing clusters that have many missing grapes

Grapes slowly disappear to raccoons

It can be easy to miss the fact that raccoons are destroying your grapes. Animals eat only so much at a time. Raccoons come back night after night, incrementally. I would notice a scattering of grapes on the ground, and gradually it seemed there were less and less on the vines. I could easily have dismissed it as squirrels or birds. I wanted to know.

I found you can rig up an old smartphone as a hidden camera, using a motion detector app, so it starts recording video when there is movement. In this way, I proved it was raccoons. They would come by, for only a few minutes, in the small hours long after midnight. They ruined much more than they ate, and the kept coming back till all the grapes were gone.

two raccoons, one in the grape arbor, one on the ground below

Raccoons, by night monitor, about 3AM

You can “attack” or “prevent”. I’ll first talk about “attack”, mostly to dismiss it; then move on to the prevention I have found most effective.

Maybe it occurs to you to shoot raccoons. Leaving aside any legality, this is hard to do. You need a gun. You need to watch you don’t shoot something you don’t want to, such as your neighbor’s windows, or your neighbor. If you hire someone to do the shooting, you are going to be paying for a lot of hours. Your agent has to stay awake and stealthy all night, waiting for that brief raccoon visit.

We assume you intend to shoot to kill. You may imagine a certain satisfaction in teaching raccoons a lesson, such as by pellet gun or some such. Most likely, the coon will just wait till you leave, and then come back. Even if you do permanently chase off that particular coon, another one will soon move in.

Much the same goes for screaming, yelling, or trying to stab with pitchforks. There is a continually replenished supply of new raccoons.

Raccoons are hard to poison. They like what they like, and are highly suspicious of anything that smells odd. The best poisons, like strychnine and “1080”, are tightly regulated. Not to mention the risk of off-target poisoning, and the continual supply of new raccoons.

Moving into the zone between “attack” and “prevent”: Electric fencing can be effective, if you can configure it right. You have to close off every point of entry, both on the ground and overhead. You want to avoid shocks to, say, your grandkids, or visitors with pacemakers. Perhaps you can power the system on a day/night timer. Not everyone appreciates the aesthetics of electric fence lines.

You can trap raccoons, but then you have the decision of whether to kill them and dispose of the bodies, or release them somewhere, which will probably already be the territory of other raccoons, not to mention other gardeners. Aside from any legality, both of these take considerable effort.

You can try repelling raccoons with something noxious. This will probably not work, as coons will just step over to get what they want. A neighbor told me raccoons hate the smell of moth balls. Well, they didn’t hate it enough to skip the grapes and cherries. The moth balls did most to repel me.

The only thing that has worked is to set up physical barriers so raccoons simply can not get to the grapes. It may not be obvious what these should be, until you understand what coons can and can not do.

raccoon in tree, showing how well they can climb

Coon in Cornelian Cherry tree

Raccoons are about as agile as cats, but with some differences. They are better climbers through brush, and have more incentive. One time I noticed raccoons foraging in a Cornelian cherry tree (Cornus mas). These trees bear small, tart berries, just what raccoons like. The trees have thin, twiggy branches, which would be difficult for a cat to navigate through. However, the raccoons, with their dexterous, five-fingered “hands” were almost swimming through the canopy.

Raccoons are about as good as cats at crossing a narrow route, such as a two-by-four or similar sized branch, spanning through space. Raccoons are much more able to cross a span they would have to hang underneath than a cat would, or would care to.

Raccoons are not so good at jumping. Cats can spring to the top of six-foot fence. Raccoons can’t get up on a trellis that way; they would have to climb. Cat’s can easily leap across a gap of a few feet. Raccoons are more limited. A gap of a three feet between, say, a tree the coons can get into and your grape supports will probably keep them out.

Raccoons can’t climb an individual year-old grape shoot, but a few vines together can serve as a ladder. Raccoons, especially small ones, might well be able to climb the few-inch-thick “trunk” of a mature grapevine. The shreddy bark gives ample claw traction.

Raccoons can climb vertical wooden posts and tree trunks. They can easily clamber through grapevines growing on a chain link fence. They cannot directly climb the walls of most houses, but they could make use of handholds like downspouts and shutters.

From this you can see that most commercial grape growing systems are cafeteria lines for raccoons. The vines are trained in vertical planes. Even if the lowermost part is above direct reach, coons can easily get up the grapevine trunks, or support posts. In a commercial operation, there are so many grapes that raccoon take might not be significant. However, in your back yard, with proportionally less grapes, you will lose your whole crop.

wooden arbor structure having metal sleeves around posts, so raccoons cannot climb to the grapes

Example, raccoon-proof arbor

Above is an example of a grape arbor that has proved coon-proof. The metal sleeves around the posts are key. They are too slippery for raccoons to climb. Notice the sleeves around the grape vine stems too. Training the vines as single stems, and nearly vertical, assures the coons can not get past.

The sleeves look like stove pipe, which I read about in an old book. Stovepipe is impossible to find any more. The sleeves are made of sheet aluminum, which you can get at any hardware store. It won’t rust out like iron stovepipe would.

I am not going to give any particular plans for such an arbor because there are so many different ways to do it. For example, you could use metal posts, that are inherently un-climbable. It’s better if you think it through yourself, based on your particular landscape.

Also, grapevines are wonderfully malleable. Like wild vines, the roots can be one place and the bearing canopy another. You could plant your vine by the dripping downspout, where there’s lots of moisture. Then you could train the vine up to your third-story penthouse patio, and have the canopy there.

The disjoint could be horizontal too. One place I saw, someone had a grape vine planted near the house. Over the years, the vine had run hundreds of feet along a fence till it finally got out from under shady trees, and bore grapes at the back alley.

When you look at the grape literature, you will see all sorts of vine training styles. Understanding how grapes grow is more important than any style. The arbor in my example has the foliage overhead, which is never done commercially. It would take too much ground space, and you couldn’t drive tractors under. But such a thing can be great for home growing. It creates a shady canopy, pleasant to sit under in summer heat.

A point easy to miss in casual descriptions of grape culture is that you chop off huge amounts of the plant each year. You basically whack it back to nothing, just the main trunk and maybe a few branches. You are not being cruel. Grape vines are good at generating great long lengths of themselves in a single season. A wild vine growing in a tree shoots out new growth to get past the additional growth the tree itself has made.

Trees sometimes lose limbs, tearing out a big section of grape vine with it. The grape vine is happy for the extra space, and shoots new growth into the opening, to get more sun. A tree has to build up enough structure to support its own weight, and therefore can’t lengthen very far each year. A vine puts its strength into growing longer, using something else for support.

A wild grape vine in a tree expects to put out new growth every year, seeking the sun. The older growth from previous years gets shaded out in the interior of the tree, and serves as conduit. To do something similar on the ground, you would have to extend your grape trellis as much as thirty feet! Grape growers centuries ago figured out it was simplest to just simulate the limb loss that tears off great chunks of grapevine. They cut off nearly all a season’s growth, so next year the vine puts out its new sun-seeking growth in the same space as before.

Grapes only produce fruit on this new growth. The stronger the new growth, the bigger the clusters of grapes. If you leave a grape vine unpruned, so the vines tangle back on themselves year after year, the new growth get ever more thin and spindly.

There are two factors. First, there are ever more points of growth. The root can only supply so much. The strength is spread over these many points, and each one gets only a little. Also, the many shoots shade each other. Alone, they could grow out faster than tree limbs, but here they are fighting each other. On such a neglected vine there will be few grapes, and they will be small.

This bearing-on-new growth means grapes avoid late frosts. When I lived in Colorado, grapes were my most satisfactory crop. Fruit trees produce their flower buds the year before. They hold them through the winter, ready to bloom in spring. In the up-and-down temperature climate of Colorado, this was a disaster, especially for the early bloomers like peaches and apricots. Spring would come. The trees would bloom. Sometimes fruit would get to the size of little green peas. Then, nine times out of ten, a late cold snap would come and kill all the fruit. No more blossoms till next year. The trees themselves grew great. They never had to waste any strength making fruit.

In grapes, however, the fruit buds are not even there till the new shoots grow out. The flower buds don’t exist yet, and therefore can’t be hurt by frost. As the shoots begin to grow, flower bud clusters form at the leaf nodes. That is, at the point a leaf comes off from the stem. These bud clusters look something like little pale rudimentary bunches of grapes.

a grape flower bud cluster, showing that it is attached to the stem at the same point as the base of a leaf

Grape flower bud cluster

These bud clusters will become your bunches of grapes. Now, here is something it took me years to notice. I assumed the grapes formed at random all along the shoots. Probably because I was looking at a tangled canopy. Finally I realized all the grapes grow at the first few nodes, close to where the shoot starts. They may skip the very first node or two, but then the grapes form at the three or four nodes after that. The shoot itself may continue growing all summer, up to thirty feet long, but no more grapes. The shoot is harvesting sunshine, and sending it down to feed the grapes at its base.

graphic showing that grapes form at only the first few nodes of a new shoot

Grapes grow only at first few nodes

There is sort of an exception. If you cut the end off the new shoot, maybe because it’s getting too long and in the way, often shoots will branch out from the part you left. These new shoots will have some tendency to make flower buds at their first few nodes. However, these get a late start, and seldom amount to anything.

new shoots growing from each node along a horizontal scaffold branch of mature grape vine

Shoots from a horizontal scaffold

This first-few-nodes idea is useful in managing your grapes. For example, you can do something like the picture above. Train the business part of your grape vine trunk as a horizontal scaffold, as shown. Each year, the new shoots will grow out of that. You can see that by the end of summer, the vines may well have grown all over the slatted roof above. However, all the bunches of grapes will be close to the main scaffold, in easy reach. Of course, you need to assure the whole thing is coon proof! Each winter, prune off everything back to the main scaffold.

(Of course this is just one of many possible ways. You can have the scaffold on top of slats or strings, and the grapes hanging through.)

Here is another thing it took me years to realize. When a grape vine starts growing in the spring, shoots try to sprout out from all over; low down, in the middle, and even from the base.

graphic showing that a grapevine will put out shoots all along its length

Shoots start from all over, especially on sunny sides

I thought I had to leave them all, no matter how much they might be providing raccoon ladders, or slapping me in the face all summer.

a bud starting to grow on the main trunk of a grapevine

Grape shoot budding from the trunk, where not wanted

Somehow, I finally got it that grape vines start many more shoots than they need. I could just break off the ones from the wrong places.

graphic showing to remove any shoots from a grapevine where they will not contribute to the desired structure

Break off any shoots not wanted

This does not take any tools. You just flick them off with your fingers as soon as they appear.

graphic showing that the shoots left to grow on a grapevine will fill out the vine

Remaining shoots fill in

The shoots left get all the strength of the whole vine. In this way you can put the shade canopy where you want.

In the same way you can shape a vine you want to want to get established. In the picture below are some young grape plants. There are a few plants close together, not yet decided which will be the one for the spot. But all of them are putting out a whole series of buds.

young grape plants with buds opening all along the stem

All but the top bud can go

If all the buds were left to grow, each shoot would grow moderately. I wanted one to grow as long as possible, to get the vine to established size. So I rubbed off all the buds but the strongest at the top.

young grape plants, showing strong growth after all but the top bud was removed

Strong growth, from leaving only the top bud

In only a few weeks, that top bud has taken all the strength of the vine, and is growing rapidly.

graphic showing that grape shoots that do not reach anything they can use for support will snap off under their own weight

Unsupported shoots will break off under their own weight

It’s important to support these new shoots. Grapes are vines. They need something to climb on. If a grape shoot grows out into space, with no support, it will snap off under its own weight when it’s a few feet long. This will happen to nearly all of them (except probably the ones you don’t want).

A rule of thumb is that the canopy of each grape vine will be something like 100 square feet. Of course vines can overlap and share the same structure, but keep in mind the size. Varieties of grapes differ in vigor. Some are delicate, and will never get that big. Others are much more robust, and will spread to several times that size. Try to research varieties you are interested in, or go look at existing plants to know what to expect.

It can be hard to believe that a small, spindly grape plant growing from a cutting will finally be a big vine, heavy with fruit. The rule of thumb here is that any trellis or arbor should be at least strong enough that you could reach up and grab on to it by your hands, and hang from it with your full weight. Slats and strings that crisscross within won’t need to be so sturdy, but a grape vine can weigh hundreds of pounds.  When fully leafed out in summer, it will also take a lot of force from the wind. A structure too flimsy will collapse, or blow down.

You, of course, do not need to build a complete structure when you first plant a grape vine. If you grow it from a cutting, it may need no more than a bamboo pole for support the first few years. Raccoons will have no interest until there are ripe grapes. But don’t paint yourself into a corner. Plant grape vines such that you at least can support and critter-proof them when they mature. Once a grape vine gets going, it can much more than double in size each year.

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One-square-meter vegetation quadrat, ultralight

This is a “quadrat”, or measurement grid, to estimate percent cover in a one-meter area. You use it in vegetation surveys.

This design is improved from the instructions originally published March 2001. When helping users, I thought people would sometimes build the old design, which costs less. However, they always went for this new one, for ease of use.

 

veg frame showing visualized lines

What this veg quadrat frame is for (click picture to enlarge)

When put together, the frame makes a square 1 meter on each side.

The four sides (or “legs”) are marked in 1/10 meter (10 cm) increments. This makes it easy for you to mentally grid up the ground inside the square.

The pink dashed lines in the picture above are your imaginary lines. As you see, these divide the whole square into 100 small squares. Each small square is 1% of the whole square.

In this example you might estimate the tree trunk takes up about a quarter of the whole square, 25% (purple solid line), or a little less. The exact way you do this would depend on your protocol.

Now, this is not about the protocol. This post is about building the equipment, so you can go out and do your study.


In a day’s work, you may move the quadrat many times. You’re constantly taking it down and putting it back together. So the leg ends attach by Velcro. They come apart easily. To assemble, you just fish the legs through the brush, touch the ends, and they stick.

One end of each leg is visually distinct from the other, so you can see at a glance which ends will connect. You don’t have to fuss, trying them all different ways.

Legs one meter long may not seem like much in open space. However hiking with them through brush, hauling them around in a crowded rig, or putting them through airport checked baggage would be awkward.

In this design, the legs are collapsible. They are made of the same ultralight rods as dome tent poles. They fold up to about one third their length. The whole frame becomes a small lightweight bundle, easy to pack and carry.

The jointed frame also means that, if there is some obstruction on setup (like the tree trunk), you just fold part of a leg out of the way.

As you read this post, if you decide these instructions are too complicated to do yourself, I offer ordering information at the end.


The core of the design is the fiberglass tent pole sections. You can buy them from:

Tentpole Technologies (“TT”)

Explain that you want sections that will be one meter long, and will fold up in thirds. If TT can look up previous orders from me (rickshory.com) you can order the same thing.

If you’re really pinched for cash, ask if they will sell you the raw materials, the fiberglass pole sections and the shock cord. You can save some money by putting in the labor to assemble them yourself.

One tent pole section, showing black and white ends

One “leg”

TT typically makes the poles with one white end, and the rest black. This is all to the good. It makes the two ends visually distinct. If you are assembling them yourself, note how they will finally fold up, to be most compact.

In order to apply the colored bands, mark the poles at 10 cm intervals. It is rather tedious to make the marks one at a time, each successively 10 cm from the last. Below is an easier technique.

Lay out a strip of tape, such as blue painter’s tape (as shown below), or masking tape. Use tape at least two inches wide, or improvise from narrower strips laid parallel. Two inches will give you enough width to arrange all four poles side by side.

jig, made of a board, to align poles for marking

Jig for marking poles

If you plan to do this a again, you can make a jig by applying the tape to a 4-foot-long board, as shown. Then you can put this arrangement away between uses. If you are only going to do this once, you can put the tape directly on a table and discard the tape when done.

lines on tape, 10 cm apart

Marks on tape

Now, you only need a short ruler to lay out marks on the tape at 10 cm intervals. (The tape saves marking up your table.)

the ends of the 4 poles, visually aligned on the tape

Pole ends aligned

When you lay out your poles, the ends may not align exactly. However, having the whole meter length at once lets you get them as even as possible. The ends may go part of a centimeter beyond the furthest marks, but this is OK. It’s well within tolerance.

sharpie pen, marking all 4 poles at once

Mark all 4 poles at once

Now, you can mark all four poles at once. Where marks fall on the white and silver sections, you only need a tiny dot to find the location later.

glint mark on black part of pole

Only a glint shows on black

However, on the black sections, the mark will only appear as a faint glint of a slightly different color quality (this is ink from a black Sharpie pen). Although you may have to hunt a bit for these marks, this is still quicker than, say, sticking temporary bits of tape to mark the places.

Below is an example of a pole after the color bands are on.

example pole showing color bands

Color banded pole

I use two easily distinguished colors, the “main” color (red here) and a “tip” color (violet in this example). The widths of the bands help visualize percent cover, but the colors themselves help keep you from losing the poles in the woods.

The main color is most important because there’s more of it. I use a color that will stand out in the environment. In leafy green vegetation, a hot color like red, orange, or yellow would be good. However, in a red desert, I might use violet for the main color instead. You may not realized how easy it is to lose equipment like this until you are actually out in the field.

rolls of vinyl electrical tape

Vinyl electrical tape

The material to make the color bands is vinyl electrical tape. Various colors are available at most hardware stores. Bright fluorescent “DayGlo®” tape would be better, but I have never found it in a field-durable form. There is a product called “gaffer’s tape” in fluorescent colors, but this is much like masking tape, and would not last long in field work.

I put the tip colors on first, to avoid mixups. You want the two ends of each pole readily distinguishable from each other, but all four poles the same. It’s easy to get confused if you start applying the color bands at random. To make the two ends most visually distinct, put the tip color at the white end of the pole.

In all the banding, wrap the tape onto the pole tightly enough that it stretches. There are a few details that will increase field durability.

tape at the start of a wrap is angled

Tape tip angled

At the start and end of each wrap, you overlap the tape somewhat. If you start with the tape tip torn at an angle (as shown), the overlap will not bulge out so much, and will abrade less. (This example wrap will go up to the next mark on the silver section, above and to the right.)

tape being torn to terminate a section of wrap

Tear tape at the end of a wrap

At the end of the wrap, if you tear the tape at an angle, this end also will be more neat.

tape tearing at an angle, ready for the next wrap

Tape breaks at an angle

The tape will then naturally break leaving an angled tear, ready to start the next wrap.

For pole junctions that will not need to pull apart, you can just continue the tape up or down from fiberglass pole sections to aluminum ferrule. However, at junctions that do need to pull apart, make two tape wraps, one on each side of the junction.

pole junction pulled apart, showing separate tape wraps on each side

Don’t tape across pull-apart junctions


If you want to add a label, now is the time, before putting on the Velcro ends. In this example, I show my web domain. You may want to put a barcode for inventory, or some contact information so lost equipment can be returned if found.

example of a label on a pole

Example label

You want your label to still be readable, even after years out in the weather. Otherwise, it’s not worth taking the trouble. In field conditions, a label just stuck on would soon be damaged or gone from moisture, abrasion and dirt.

labels packing slip

Weatherproof labels

A paper label would quickly degrade. I use these weatherproof labels, item number OL1825LP, from onlinelabels.com. Note that these are very small labels. You do not have much room on a slim tent pole.

tubing being cut

Shrink tubing

Even these tough labels would break down or wear off if left exposed. I cover the labels with transparent “heat shrink tubing”, often used in electronics to insulate wires. The size is 0.375″ (9.53mm) diameter. It is available from DigiKey, part number A038C-4-ND. It come in four-foot lengths, which you cut into short pieces to cover the labels. A piece about 2.4″ long is good for covering each label. You can cut 20 of these out of each four-foot length.

tube sleeved over label

Tubing in place

Apply a label and slide the shrink tubing over it.

tubing above a candle flame, shrinking into place

Heat shrinking

Heat the tubing to shrink it in place. Using a candle, as shown here, you can “roll” the pole as you gradually feed it past the flame. Start from the larger aluminum ferrule end to avoid trapping any air bubbles. If you take care to keep the tubing above the tip of the flame, you will not have any black soot.


I use two different colors of sticky-back Velcro, to accentuate visual contrast.

roll each of black and white Velcro

Sticky back Velcro

The hook Velcro of one color goes on one end of each pole, and the pile Velcro of the other color goes on the other end. It does’t matter which goes on the “tip” end, as long as you are consistent for all four legs. That way, you know at a glace “opposite” ends will always stick together.

Velcro strip being cut to 5.5 inches

Length of Velcro

If you cut one length of Velcro 5.5 inches long, this will supply all four pieces you need for the legs.

Velcro strip 5.5 inches long being cut in 4

Divide into 4.

You can fold this and cut it in half, then cut each of those in half again.

cable ties being made into open loops

Prep cable ties

The Velcro backing is pretty sticky. However, in the dirt and wet of field work, it would come loose. Hold it on with small 4-inch cable ties. It is convenient to prepare these by partially inserting the tail, to make small loops. Then, they will be ready to use when you stick on the Velcro.

Velcro section being wrapped around pole end

Stick Velcro on

Wrap the Velcro sections around the ends of the poles. The Velcro will overlap slightly. Note that the exact point of one-meter length on the pole is about a centimeter in from the end. This lines up with the center of the width of the Velcro.

cable tie pulled tight around Velcro, tail of tie being cut off with wire cutters

Finish

Slip on a cable tie, pull it tight, and cut off the tail.


bundle held by fingertips to show how light weight

Finished bundle

The finished set is convenient to be bundled up with a rubber band.

pole end with rubber band around

Band stowage

While you’re using the frame, you can put the rubber band around a leg end. There, it will be handy when you pack up.

bundle on scale, showing weight 9.6 ounces

Bundle is light in weight

The entire set weighs only about 275 grams, less than 10 ounces.


I developed this while working on federally funded research grants, so the design is in the public domain. You can build a set for about $35 in parts.

People also request to buy the complete sets from me. I charge $192 per set, plus $21 shipping. Two or more sets get free shipping. Ordering details are at rickshory.com.

close-up of two winter jasmine flowers, one with five petals one with six


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Garden idea: Fake your forsythia

This has already fooled two experienced gardeners. It looks like forsythia. It is forsythia. But wait! This is still January. Way too early for a forsythia bush to be blooming! What gives?

winter bare forsythia bush with winter jasmine growing in it

Forsythia?

Ok, Ok. The little yellow flowers are really winter jasmine (Jasminum nudiflorum). That plant is growing up through the still-bare branches of the forsythia (Forsythia × intermedia).

I’ve always liked winter jasmine. The bright yellow flowers are a cheery reminder of sunshine for our gray winter landscapes. But how do your grow the plant, with any sort of grace?

If you let it sprawl, it gets all over into everything, with the grass coming up through it. I’ve seen it trimmed into a low mounding hedge, but that’s a lot of trimming. At the Chinese Gardens downtown, they use it effectively, overhanging the edge of a pool, with the sight of it reflected in the pond surface. But I don’t have any water features. You can train it up a trellis. But then you have nothing but nondescript green viny twigs there all the rest of the year.

I got the idea for this from a friend’s house, where he did have his winter jasmine trained up a sort of columnar trellis. Nice, I thought, but a lot of work. Let’s do double duty. The other part of the idea came when someone mistook winter jasmine for forsythia.

This would never have occurred to me. To a botanist’s eye, of course, forsythia and winter jasmine look nothing alike. The winter jasmine has green twigs while those of forsythia are brown. Winter jasmine flowers are five- or six-petaled, while forsythia has four. This was a revelation. That, to the public, these two plants could be mixed up with each other.

close-up of two winter jasmine flowers, one with five petals one with six

Winter jasmine

Well, I thought, if they see them as the same, let’s work with that. I trained the winter jasmine to grow up through the forsythia. This was easy — just drape the drooping jasmine twigs up through the forsythia branches, once or twice a year. Chop off any extras that get too much.

So, now we get to enjoy this forsythia bush “blooming” two months early.

By the way, I decided I did not care to have my forsythias as big wild things, taking over acres of landscape, as they try to do. So, I have trained them to be trees. When they were starting, I did not allow any growth below a certain height, about a foot off the ground. This established a trunk. Now, I just break off any shoots that try to come up from ground level. I can use the space below them for other things, like spring bulbs. And maybe a few stray branches of winter jasmine.

grape cuttings, rooting in jars of water


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Growing grapes, part 1, propagation

Growing a few grape vines around your house is a different proposition than a commercial vineyard. Much of the information you will find is geared towards large-scale production. In this post, I am going to concentrate on backyard growing. There are significant differences in focus, both in propagation techniques, and in training the vines.

 You start a new grape vine from a “cutting”. A cutting is simply a section of grapevine. You get roots to grow from the bottom, and leaves to grow from the top, and then you have a new grape plant. Grapes will grow from seeds (except of course seedless grapes), but you’re not sure what you’re going to get. To propagate a certain variety, you want to use cuttings.

In grape growing, you prune off a considerable amount of vine each winter. This naturally provides material for cuttings. Most information about grape propagation is geared towards these winter cuttings, made from dormant, leafless vines. I’ll discuss these, but also alternatives.

To start a sizeable vineyard, a grower would, of course, be dealing with a great number of cuttings. The easiest way to get these is to section up the prunings from existing vines. So a lot of grape propagation information concerns the mass organization, storage, and rooting of these winter cuttings. On a backyard scale, however, not all these points apply.

To divide out a section of vine to make a cutting it takes, of course, two cuts. One is the lower cut, which will be the bottom of the cutting, where roots will grow. The other is the upper cut, the top of the cutting, from which the leaves will develop. In large scale propagation, it’s handy to be able to tell these ends apart at a glance, and so a tradition has come about: The lower cut is straight across the vine, just below a node. The upper cut is angled, just above another node. If you receive grape cuttings, they will usually be done this way. If you are dividing up grapevines to make your own, it’s a handy grammar. However, you don’t have to strictly follow this.

Cuttings are usually made with at least three nodes, such as the one on the left in the picture below. This gives nice strong cuttings.  You may be surprised how long three-node cutting are. You may have a hard time finding a place to store them. You may be bringing some home in your airline luggage. You may have difficulty digging a hole deep enough to plant them. So, if you are making cuttings, and length is a problem, you can make two-node cuttings, like the one in the middle of the picture. (Click on the picture to enlarge.)

Three grape cuttings, one with three nodes, one with two nodes, and one with four nodes.

Grape cuttings: 3-node, 2-node, and 4-node.

It’s fine to have more nodes, such as the four nodes of the cutting on the right.

I have had one-node cuttings grow, by accident. When I prune my grape vines in winter, I just chop up the small stuff with my pruners, and let it fall on the ground. Usually, a few pieces happen to land among the garden plants just right, and get watered just right, so that some time the following summer they start to grow. Roots come out below the node, and the node bud opens out into leaves. So, if one little section of grape twig is all you can get, you might be able to grow a vine from it.

small section of grapevine, with only one node, shown as an example of how small a section can serve as a cutting

Even a small piece like this can grow

Commercial propagation consists of bundling up the grape cuttings for winter storage, and then getting them to grow in the spring. You may read about technique such as burying them in sawdust or sand, using rooting hormones, burying bundles upside down, and using bottom heat in a propagation bed. I’ll explain what these are about, and how they apply, or don’t, to home propagation.

The basic issue of storage is to keep the cuttings alive, and keep them from sprouting too soon. The main reason cuttings would die is from drying out, thus the burying in damp sawdust or sand. This is reasonable for large bundles, but there is no reason for you to go get these materials for only a few cuttings. You can just keep your cuttings in vegetable bags, like any other produce.

As I’ll describe later, you can start your cuttings growing in the winter. But then you are faced with the problem of keeping the plants healthy until spring when they can go outdoors. So, unless you particularly want to do this, you should keep cuttings cold, so they stay dormant. If you have only a few cuttings, you can keep them in your refrigerator. For more, you can store them outside.

Freezing is not particularly a problem for grape cuttings. Any variety you are planning to grow, which is hardy in your climate, can stand up to your winter temperatures. However, in continental climates, winter weather is often very dry. Therefore, grape cuttings left out on the open ground can dry out. A convenient way to both avoid this, and keep the cuttings organized, is to slip them into plastic vegetable bags, and tuck these under a few inches of dead leaves or other mulch. In a mild, wet-winter climate like the Pacific coast, you don’t even need to bury them. Grape cuttings may be too long for a single bag. You can use two bags, one “telescoped” inside the other.

grape cuttings in plastic bags, showing that if cuttings are too long for one bag, you can use two bags, one overlapping the other.

Bags for long cuttings, one overlapping the other.

If you have plenty of cuttings available, the easiest way to start a grapevine is simply to plant a number of cuttings close together where you want your vine.

eight grape cuttings planted close together

Grape cuttings planted

Here, I put eight cuttings close together. This was in early March, but you can do it any time in winter the ground is not frozen. I did not use any rooting hormone, or other treatment. The ground was so stony, I could not plant all of them as deep as ideal, which would have been with only the tip above ground.

Still, six of the eight cuttings grew. This picture is from the following December.

the same eight grape cuttings the following fall

Grape cuttings after a season’s growth

The point of this technique is that, even though some of the cuttings die, you still get a grapevine going. Just pull out the dead ones and the extras, and leave the strongest. If you have lots of cuttings, which you will if you have an existing grapevine, or know someone who does, this is by far the easiest way to start a new one.

Incidentally, there does not seem to be any pattern to which cuttings take hold. In this case, the two that died, out of the eight originally planted, looked just as strong and promising as the ones that grew.

the two cuttings that died, of the eight originally planted

The two cuttings that died

This multi-cutting method does not, of course, make sense for a large-scale planting. For that, you want to be pretty sure each cutting will grow, so you can line them out in rows and end up with a vineyard. From cuttings just stuck in the ground, I have always had more than 50% grow, typically 75%. But that’s nowhere near good enough for commercial production.  Filling in 25% gaps would be a lot of effort. It would be almost as much work to take out the extras, from mutliple cutting planted at each spot.

The propagation techniques you come across in the grape literature are all about increasing the odds per cutting, so you get one grape vine from each thing you plant.  For home-propagating a few vines, these techniques may not apply. If you have lots of cuttings, you can get away with a low per-cutting success rate.

But what if you have got ahold of only one precious cutting, which you absolutely must make grow? Maybe you had to pay a lot for it, or it was all the source could spare. Maybe it came from halfway around the world, and you will never be able to get another. I stumbled on a simple, inexpensive technique that, for me, has given 100% success: Root them in water.

Nowhere in all the propagation literature had I ever heard of rooting grape cuttings in water, but it works quite well. It allows you to carefully monitor progress, as well as being interesting to watch. It would be far too much fuss for mass production, but it’s ideal for a few.

grape cuttings, rooting in jars of water

Grape cuttings, rooting in jars of water

Just put your cuttings in jars that have some water. Change the water if it gets too murky. Because there is plenty of water, the cuttings cannot dry out and die, unless you let the water dry up. You can put the jars outdoors, in direct sun, so any leaf growth is firm and strong.

grape cuttings that have been in water, laid out to show the details of roots

Cuttings that have been in water, growing roots.

If you look close at the picture above, you will see that the source of the cuttings did not much follow the “grammar” of number-of-nodes, and straight- and angle-cuts. But the cuttings are rooting just fine. The conventional wisdom is that grape cuttings grow roots from the nodes. However, as you can see, the roots are coming from the bottom of the cuttings, ignoring the nodes. Cuttings do have a tendency to put out more roots near nodes, but this is by no means strict.

Cuttings with roots at this length are ready for planting. Short roots like this are called the “rice” stage; little white rods like grains of rice. Roots let to grow to the “spaghetti” stage are more prone to break off. Longer roots don’t give much advantage in water absorption. They have to develop a new set of root hairs, from additional growth, before they can supply much to the plant.

Virtually always, cuttings in water will have leafed out by the time they root. This is the main thing you will have to fuss over.

Roots absorb water, and leaves expend it. A typical scenario is this: Grape cuttings are planted out during cool, wet weather. They look fine, the foliage fresh as lettuce, as long as the rains remain. Then, one day, the weather turns hot and sunny. The roots can’t keep up, and the leaves shrivel. In the extreme, the whole thing may die. It can also happen that the leaves shrivel up, but the cutting hangs on till it finally makes enough root growth to put out new leaves. Although a cutting like this may survive, it will be set back, and not make nearly as much growth in its first year as a cutting without this hardship.

What to do? Simply shade a newly planted cutting until it adapts. You can rig up special shaders in various way, but often the simplest thing is to just put a lawn chair on the sunward side of a new grape cutting. This would be on the south side in the northern hemisphere, on the north side in the southern hemisphere. A cutting can handle as much indirect sky light as there is, and it won’t have much trouble with morning and evening sunshine. It’s direct mid-day sun will that will dry it out.

You only have to shade a new cutting for a few days, or a few weeks at most. Soon the roots extend and send more water up to the top. The leaves grow and send food down to the roots. And the plant is in business.

Up till now, we have been talking about cuttings from winter-dormant vines. I found by accident that you can root green leafy summer shoots.

Once, I had a chance to get grape cuttings of a variety I wanted to try, but it was midsummer, not the usual time. I kept the cuttings in water, intending to study them. After some weeks, I noticed they were growing roots.

cuttings taken in the summer that have grown roots

Summer cuttings may drop their leaves by the time they grow roots.

This can take quite a while. In this case it was September, and by then the shoots had dropped their leaves. But I had a rooted cutting I could plant.

detail of roots on summer grape cuttings

Roots on summer cuttings

Later, I saw summer grape cuttings being propagated in a university research greenhouse. These were two-bud cuttings, and half of each leaf had been removed to reduce water loss. The cuttings were under an “intermittent mist” system, which is a method that works very well, but it rather complex to set up.  So, if there is a variety of grape you want to try, and the only time you can get cuttings is when they are fully leafed out in summer, you can get fairly good success by rooting them in water.

For various reasons, you may need to transplant a grape vine. If at all possible, do this while the plant is dormant and leafless. Leaves lose a lot of moisture.

In my experience, you can transplant a grape vine of any size, but a mature plant will be set back for about a year. It will take hold, as though it were a large, rooted cutting, but it will put out less growth the first year after transplanting, and produce fewer grapes. A large grape vine can be quite physical to wrangle, so take this into account in deciding whether you want to move a vine, or simply start a new one. You can have grape vines in full production, from cuttings, in three years.

Below is a picture of a one-year-old grape plant, dug up for transplanting. This grew from a cutting merely stuck in the ground, with no other help than regular watering. It is typical for a vine to make only a few to several feet of top growth the first year. It’s developing lots of roots, getting ready to take off following year. Now, there is more root than top.

one-year-old grape plant, dug up for transplanting

Grape dug up for transplanting.

Grapevines typically have a root system that consists primarily of relatively few long, snakey roots, rather than much of a root ball. Notice the plant in the picture: Even though more roots started from near nodes, the strongest root came from between nodes. This is just the way it happens sometimes.

Grapes are mostly woodland plants, where their roots have to compete with trees. Their roots grow long, to seek out what they need. For the backyard grower, this means that after a few years, you are going to be finding your grapes’ roots many yards away, mining water and nutrients from whatever garden beds they can get into. Be aware of this when choosing a planting site.

Grapes do fairly well with their roots under a lawn, but be aware of what this can mean. For some years, when I lived in a dry climate in Colorado, I grew grapes on the chain link fence that bordered my neighbors. The neighbors were much more lawn conscious than me, so the grapes put most of their roots over there, where they could get more moisture. Then, at one point the neighbors were going to sell their house, so in order to spruce up the lawn, they sprayed weed killer. The grapes took it up, and nearly died!

You can of course grow grapes in pots, but they are not naturally adapted to this.

grape vines growing in pots

Potted grape vines

This picture is of some grape vines, in their first summer, developing from rooted cuttings. It is only July, and the plants are already getting to unmanageable size. If they were in the ground, the roots would have extended at least as long as the vine top growth. But here, the roots are having to spiral around and around inside the pots. These plants are sustained by drip irritation, and their water demand is only going to increase. If the moisture were ever interrupted, the plants would be severely stressed.

Of course nurseries only sell grapes as potted plants. Typically, these vines are fairly small. If they had been let to grow large in pots, they would be significantly potbound. They are going to have to stretch out their roots some time. If possible, let them do it from the start.

Now, I would like to demystify some of the grape propagation information you are likely to come across. Often, terms are given without any definition, and techniques are stated without any reason why.

You may come across the term “callus” in grape propagation. Callus is whitish cauliflower-like growth that plants may form in the process of re-organizing their tissues.

callus on the ends of grape cuttings

Well developed callus on grape cuttings

Some varieties of grape develop a considerable amount of callus, which serves as a signal that roots are on the way. However, others grape varieties make no visible callus before roots pop out.

a grape cutting that has roots, but developed little callus before rooting

Some cuttings root with little callus

The propagation literature may recommend a certain operation to “callus” cuttings; that is to nudge them towards creating roots. This is what “callus” means, used as a verb. Keep in mind there may or may not be any visible change.

The main reason grape cuttings fail and die is that leaf growth outstrips the moisture roots can supply.  Most of the details of large-scale grape propagation are to get around this problem, so a higher percentage of the cuttings succeed, and a vineyard planting will requires less fill-in afterwards. Again, this is less important for a home grower, but it’s the reason behind the recommended methods.

A bud is ready-made. All it needs to do is open and put out leaves. However, for a grape cutting to grow roots, it has to re-organize its tissues to create these. Different varieties of grapes vary in the time-lag it takes them to do this. In the extreme, you can get a leafed-out cutting that still has no roots at all. To improve on that, you want to speed up the formation of roots, relative to top growth.

Rooting hormones act as “auxins”, which are a type of naturally occurring plant hormone. Plants produces auxins in their growing shoot tips, and the auxins are transported downward through the stem. If the stem is cut off, the downward travelling auxin accumulates at the cut end and stimulates the tissues to re-organize into roots. There’s more to it, but that’s the general mechanism.

This explains why reluctantly-rooting grape cuttings will finally get around to growing some roots when the buds open. The growing shoot tips produce more auxin. This is how the water method works. It provides life support until roots grow, no matter how long it takes.

Rooting hormone is simply externally supplied auxin. Much like natural auxin, it moves downward through the stem and accumulates at the lower cut end. The usual mode of application is by dipping the rootward end of a cutting into a powder or a solution, so the hormone starts near to where it’s needed. Then the cutting is planted in a soil-like medium.

It’s an open question whether rooting hormone would help cuttings root in water. Would the auxin accumulate in the water and help? Or would the water dilute it, and lessen its effect? From the product standpoint, this is usage beyond its specifications. From the plant standpoint, grape cuttings root fine in water without it.

Another aid to rooting is “bottom heat”. All else being equal, plant life processes go faster at warmer temperature. If we were to keep the bottom of the cutting, where we want roots, warmer than the top, the lower end should grow roots while the top is still dormant.

This is, in fact, exactly what happens. Bottom heat is much used in commercial propagation. However, when you start looking into it, you will find it amounts to considerable outlay in effort, equipment, and expense. You will have to decide if the investment is worth it for a few grape cuttings.

The idea of burying bundles of grape cuttings upside down for some period of time is to use nature as bottom heat. Since soil warms in the spring from the top down, this will make the root ends of the cuttings warmer than the tops. This technique could tip the balance in large-scale commercial production, if the weather and climate cooperate. However, think for a moment what’s involved in digging holes big enough to bury long bundles of grape cuttings. Not to mention, digging them all up later, to plant right-side-up. There is no reason to do this, to start a few new plants.

I have tried various things with water, to get roots while buds were still dormant. One time, I used winter-dormant cutting in late fall. I put them in water, in an indoor growth chamber about 70 degrees F. I knew that most deciduous plants have a “chill requirement” and the buds won’t open until a certain time period of cold weather has elapsed. I figured I could get roots, with the buds still closed.

Well, the plants had their own idea. The cuttings rooted well, but the buds opened too. By January, I had healthy, actively growing grape plants. Again, unless you particularly want these decorations, you should keep your cuttings cold, and dormant, till spring.

I tried the bottom-heat idea, with water. My system involved an aquarium heater, in the refrigerator. The bottom ends of the cuttings were held at about 78 degrees F, while the tops remained about 40F. This worked, to some extent, but it was a huge amount of trouble.

Continued in part two, grape vine training.

apple seeds germinating


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Germinating fruit tree seeds

There is a huge amount of disinformation out there about how to grow fruit tree seeds. Rather than going into all that, this post is about how to do it.

This is not even an experiment. I’ve been growing tree seeds for decades, and I know how it will turn out. This is more a test, to demonstrate the techniques.

I saved a handful of apple seeds, from some random apples I used to make applesauce. Later, I’ll discuss differences in species and varieties, but ordinary apple seeds make a good demonstration.

I divided the seeds into three approximately equal batches, of about 23 seeds.

16-01-22-3-batches

The first batch was the “control”, or no treatment. I planted these in a pot of dirt, same as you might plant flower seeds.

16-01-22-control

This was on January 22, 2016.

I kept the pot moist, in normal warm room temperature. At the end of the test, May 4, 2016, there was no difference. Not one had grown.

16-05-04-control-check

If you try this with a large number of seeds, you may have one or two random seeds sprout, but this is not the way .

Next, the “freeze” batch, I put overnight in the freezer.

16-01-23-after-freeze

The next day, I put them in a small ziplock bag with damp sawdust, and stored them in the refrigerator.

16-01-23-freeze-bagged

I checked on them periodically. In this check on April 1, 2016, none have grown.

16-04-01-freeze-check

At the end of the test, May 4, 2016, none had grown.

16-05-04-freeze-check

Looking close, the moisture around the seeds is becoming milky. The seeds are starting to rot. They are dead, and have been since they were frozen.

16-05-04-freeze-detail

This is one of the misunderstandings. People hear that seeds need cold to germinate, so they freeze them. As if freezing will “break” dormancy, like shattering ice. No.

If seeds are completely dried, some species can survive deep cold, but it only holds them in suspended animation. It does nothing to make them germinate. Usually, it just kills them, as you see here.

For the “chill” batch, I put them in a ziplock sandwich bag with a little damp sawdust. I put this bag in the refrigerator. These seeds need moisture and oxygen to germinate. Polyethylene, the plastic most ordinary plastic bags are made of, is permeable enough to oxygen that this works fine. You can zip the bag closed so the seeds don’t dry out. You do not need to leave the bag open.

16-01-22-chill

In this check, on April 1, 2016, you can see that some seeds are starting to germinate.

16-04-01-chill-check

Germination is a gradual thing. I judged that a seed had “germinated” if the root tip coming out was longer than it was wide. So, on this date, I counted 3.

16-04-01-chill-detail

In the next check on April 15, 2016, more had germinated. I replaced the sawdust with a damp paper towel, to make things easier to see. This works just as well as sawdust. If you don’t need the see the seeds, you can use peat moss, sand, soil, crumbled up autumn leaves, etc. If you’re doing a lot of seeds, you can mix them in the bag, and then plant the whole mix once the seeds are germinating.

16-04-15-chill-check

 

If you count the seeds, you will notice I did not put back the 3 that had already sprouted. The purpose was to demonstrate germination, not to grow the seeds. If you want to grow the seeds, you can plant them as soon as they sprout. They don’t need cold any more. In fact, cold only slows them down. This is natures way of easing the seedlings into springtime. Chill breaks their dormancy, but then the cold temperatures keep them growing slowly, so they don’t pop up and get hit by late frosts.

Going by my criteria, I did not count the seed in the lower right corner to have “germinated” yet, as its root was not long enough. So I counted 5 more germinated on this date, for a total of 8 so far. But as you will see, it makes little difference in the final tally.

16-04-15-chill-detail

By May 4, 2016, all the rest of the seeds had germinated.

16-05-04-chill-check

Here’s the numbers on this test. None of the seeds grew except those in the “chill” treatment.

16-05-05-1-data-table

The magic is holding the seeds at a temperature above freezing, but below about 40 degrees Fahrenheit (4 degrees Celsius). Your ordinary home refrigerator is the correct temperature range. How do you know? If it were too cold things would freeze and if it were too warm your food would go bad. If your refrigerator is working normally, it’s perfect to cold-treat seeds. This is what has happened when you cut open and apple and find seeds sprouting inside. The apple was kept in cold storage, and the period of refrigerator temperature satisfied the seeds’ chill requirement.

The seeds need to be imbibed with water, but not under water. Immersed in water, they would not get enough oxygen.

These are like the conditions a seed would find, buried in the surface layer of soil, through the winter. Even in continental climates, where air temperatures go extremely low, the soil a short distance below the surface seldom freezes so cold.

Here are the numbers on the “chill” treatment, with the dates translated into elapsed time. Chill requirements for plants are often expressed in hours, so I’ve included the elapsed time expressed as hours as well as days.

16-05-05-2-percents

Notice that nothing visible occurred for more than a month! It’s as if the seed has a little hourglass inside, which runs down while the chill conditions are met.  If it’s too warm, the hourglass stops. If it freezes, the hourglass stops. But after enough accumulated hours, the seed grows.

16-05-05-3-chart

Notice that this is not abrupt, but in most batches of seeds, once it starts it goes pretty quick. This is how nature hedges her bets. If some seeds came up too early and got killed, there would be stragglers to take their place. On the other hand, if the early ones got a good head start and took over more space, the next generation would drift towards lower chill. In tree species that have a substantial north-south range, local populations have adjusted themselves to the best chill requirement for their conditions.

Plants use the same chill mechanism to “know” when to leaf out. It correlates with seed chill. That is, for two of the same kind of plant, except with different chill requirements, the one that needs less chill to germinate from seed will need less chill to start leafing out each spring. All else being equal, it will bloom earlier too.

This explains why certain fruits are notorious for getting their blooms frosted. Peaches have a low chill requirement, and apricots even less. Evidently they originated in parts of the world with cold winters, hot summers, and not much transition (chill) in between. Brought to North America, where the weather has all sorts of wild swings, they get their chill requirement at the first breath of spring. They bloom out, then get snapped by late frost.

Why haven’t they adapted? They never needed to. If you grow these seeds, you will find them very “easy” to germinate. Everyone who ever cultivated them did too. The grower planted a bunch of seeds, and the first sprouts to pop up tended to get planted out in the orchard. This, of course, selected for low chill. The trees did well enough, and if the blooms got frosted too often, well, that region would not be known for apricot production.

If you wanted to develop, say, a late-blooming apricot, you could use this approach. Plant a lot of seeds. Say you want ten trees. As the seeds germinate, pot them up, but when the eleventh one germinates, pull up the first one and plant the eleventh one in its place. Keep on doing this. Eventually, you will end up with the slowest to germinate, high-chill individuals. It might take generations, but finally you would have a late-blooming apricot.

This chill technique for germinating seeds works for most mid-latitude tree crops: apples, pears, peaches, apricots, cherries, plums, persimmons, almonds, chestnuts, walnuts, hickories, etc. It may be hard to believe a tender root tip can break its way out of a rock-hard seed like a peach pit or a walnut, but it does.

Most trees that ripen their seeds in the fall need chill. These include ashes, beeches, and some maples such as sugar maple, Norway maple, bigleaf maple, and vine maple. Tree seeds that ripen in the spring tend to have no chill requirement. They are ready to germinate as soon as they fall. These include elms and certain other maples like silver maple, and red maple. A number of leguminous (bean family) trees, such as locusts and mimosa (Albizia), have no chill requirement. Instead, their germination is inhibited by a water-impervious seed coat.

This chill technique is sometimes called “stratification”. This is from a traditional method of putting layers (“strata”) of sand and seeds in flowerpots or lath-bottom boxes, and leaving these sunk in the ground over winter. You can see why it works. Winter moisture keeps the seeds imbibed. The upper layers of soil maintain the proper chill temperatures. The sand makes it easy to separate out the sprouting seeds when it’s time to plant them in nursery rows. If you do it this way, put bricks or something on top of your flowerpots, to keep squirrels from messing with your seeds.

Seeds that need chill will, of course, germinate just fine planted directly outdoors in the fall. However, there is liable to be a lot of grass and weeds also growing by spring when they come up. You may have a hard time spotting the seedlings, or remembering where they were.

If you want to grow a lot of seeds this way, plastic bags may be easier than pots. Collect up your seeds as they come along, and keep them so they do not completely dry out. For example, cherries ripen in early summer. As you use the cherries, put the pits in some loosely lidded container or a plastic bag with something to keep them a little damp, such as moist sand, soil, peat moss, dead leaves, or sawdust.

If you put them in the refrigerator in the summer, they are likely to have their chill requirement met by fall, and germinate as winter is coming on. If this is what you want, growing them indoors all winter, go for it. But for a more natural cycle, put your seeds in a plastic bag and bury it a little below the ground surface, or under some dead leaves or sawdust. Then, the seeds will stay at ambient summer temperatures until autumn, and their timers will not start running down yet.

Be sure you have your seeds buried before things freeze hard. One time, I had a bag of peach pits out on top of the ground, and a November cold snap went to single digits. All these seeds were killed, but the ones buried just a few inches were fine.

As autumn comes, the temperatures will start dipping into the chill range at night, and the seeds’ timers will start ticking. As the weather gets cooler, the seeds will accumulate more chill hours each day. In midwinter, the seeds may go slightly below freezing, and their timers will stop. But as spring comes, they will resume. As each seed germinates, it will start to put out a root. Keep checking them. If left too long, the roots will be all tangled together, and the seeds will be hard to separate out to plant.


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Germinating ginkgo seeds

I had never grown ginkgo (Ginkgo biloba) seeds before, so when I noticed them under a tree in late November, I collected some to investigate.

I had a ziplock bag with me, and filled it up with the “fruits”. Botanically, these are not fruits at all, but that’s another story.  It’s well known that these smell bad, at least when freshly fallen. The odor is described as rancid butter, or dog shit. However the autumn weather had been torrential rain, and the scent was all leached away.

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It was about a month before I got around to the seeds. Meanwhile, I left the bag outdoor so the “fruits” would stay moist in the wet autumn weather. On December 31, 2015, I started my experiments.

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The “berries” were single or in pairs, on stalks.

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When I peeled off the fleshy covering, inside were the seeds.

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I gently cracked them open.

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Inside were the kernels.

I knew that, botanically, ginkgo seeds are not like angiosperm seeds, where the embryo plant grows to a certain stage, and then various inhibitions come into play to keep it dormant. The ginkgo life cycle is more like a fern.

The brown dots on fern leaves shed microscopic dust-like spores. These drift on the wind. If a spore lands in the right conditions of moist soil, it grows into a prothallus. Prothallii are quite common, once you learn to spot them. Here is a picture of some that appeared in one of my potted plants.

gb060_prothallus

The dark green membranous thing in the lower right is the prothallus. It looks like a bit of seaweed washed up, that hasn’t dried out yet. It grew from a drifting spore, by the grace of drip irrigation watering that kept the soil continuously moist. The prothallii of most kinds of ferns can only develop in continually moist sites (this is where to look for them), though some cliff ferns have prothallii that can survive drying out.

With good luck, the prothallus grows to full size, which is only about a quarter inch across. When mature, it develops male and female gametes on its underside. When there is enough water, the male ones swim to the female ones, presumably sometimes to a different prothallus for genetic mixing. The fertilized zygote develops into a lump of cells, nourished at first by the prothallus. When this embryo plant gets big enough, it puts its first root down, its first leaf up, and grows into what most people recognize as a fern. The lighter green leaves towards the top of the photo are such a baby fern. It is growing out of a different prothallus than the lower right one, but it is behind the leaves and hard to see.

Other spore plants, like horsetails, also produce these gametophytes. “Gameto-phyte”, because it forms the gametes. The horsetail gametophytes I have seen are also green, but fleshier. Still other spore plants, like club mosses, supposedly produce lumpy gametophytes underground, but I have never seen them. The general plan is, the spore grows into a gametophyte, which only does two things: Produces gametes, and then nurtures the main plant till it gets on its own.

It doesn’t seem fair. The fern gametophyte has to eke out a living as a miserable prothallus, harvesting enough sunlight to grow and start the next generation, while desperately living on the edge of death by desiccation. But the main fern plant is big and robust, with roots and tall fronds, and all. Why couldn’t it help out the next generation of gametophytes with some of its bounty?

This is evidently what ginkgoes have done. Instead of casting spores to the wind, the ginkgo holds them on little stalks. As a spore develops into a gametophyte, the tree feeds and shelters it. Instead of having to live free or die, the ginkgo gametophyte has a pampered life. How the gametes get to it from a different gametophyte is another story, but the hint is: Pollen.

So, I looked at these ginkgo kernels, and I thought: When I want to grow ferns, I get the spores, and set up moist mellow conditions, and by and by they to grow into prothallii. Then I just wait. In their own sweet time, they get around to the gamete thing, and then start with the lump of cells. Once the first fern leaf appears, I’m home free.

So, here with this ginkgo seed, it’s all been done for me. No fragile prothallus to fuss over. This gametophyte doesn’t have to be green because it doesn’t need photosynthesis. It was well provisioned by the tree. So, instead of thin and membranous, it’s fleshy and packed with stored food.

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I sliced some of the ginkgo kernels open, and there were the developing plant embryos. This was exactly analogous to the lump-of-cells stage of a fern plant on its prothallus.

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The ginkgo plantlets were different sizes. Some were about half the length of the seed, but some were as short as a quarter the seed length.

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Some gametophytes had no baby plant at all. I guess sometimes the male ginkgo is shooting blanks.

So, I thought, maybe it’s the same as growing ferns. You just set them up and let them take their own sweet time. They don’t need light in this case, but they probably want to be moist.

I divided my ginkgo seeds into three groups. I put them in ziplock sandwich bags with damp sawdust. Probably sand would have worked as well, or moist leaves, or even torn-up wet strips of paper.

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One bag I kept about 40 degrees. This was outdoors in an unheated garage. It might have occasionally got frosty, and sometimes as warm as 50 degrees.

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One bag I kept about 60 degrees. This was indoors, on the floor of the basement.

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One bag I kept about 80 degrees. This was in a plant growing room with warm lights.

On February 3, 2016, I checked on them. This was after about a month, 34 days. All three had been going for the same length of time.

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I picked three seeds at random out of the 40 degree bag. The embryos had grown some, but not much. They averaged about half the length of the seed.

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I picked three seeds at random from the 60 degree bag. Here, the embryos were definitely bigger, about three fourths the length of the seed. If you can see, in the middle one, the root is starting to push out of the gametophyte.

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When I came to the 80 degree bag, I did not pull them at random. I grabbed the first three that were obviously clambering to get out.

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It looks like ginkgoes have something like hypogeal germination. That is, the seed does not get pulled up above ground. The embryo elongates to push the leaf bud outside the seed, along with the root, and then a shoot grows up from that. The upper ends of the “cotyledons”, or whatever they are, stay inside the seed, to continue feeding from the gametophyte.

So, it appears to me that ginkgoes do not have true seed dormancy, as angiosperms do. To avoid coming up too early, in the midst of winter, the ginkgo embryo simply develops very slowly, as long as things stay cold. Instead of counting chill hours, they just pace themselves. When spring comes, they speed up. The warmer it gets, the faster they grow.

If you want to grow ginkgo seeds, just keep them warm, and they’ll sprout. They absolutely do not need to be frozen. Deep freezing would probably kill them. Drying out would probably kill them too. After all, they are just gametophytes.


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Germinating mimosa seeds

I thought that the main germination inhibition for mimosa (Albizia julibrissin) was the water impervious seed coat. This is an experiment to check that.

I found some mimosa pods that had just fallen from the tree. Their structure was papery valves (the flat sides), with wiry reinforced edges.

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Mimosa pods

It was evident their dispersal mechanism is to be blown about till the wiry edges wear out, allowing the valves to peel apart and drop the seeds. This goes along with the idea that the seeds are blocked from germination until their hard coats are breached, either from erosion by gritty soil, or long rotting in humus.

I took out ten seeds.

ten mimosa seeds

Ten mimosa seeds

I put them in water to soak.

ten mimosa seeds soaking

2015-11-24 08:10

About 24 hours later, two of the ten (20%) were imbibed with water.

20 percent imbibed by 2015-11-25 06:46

2015-11-25 06:46

This verified the seed coat was impervious enough to water to prevent absorption.

seeds, imbibed and not

Compare imbibed to not imbibed.

Breaching an impervious seed coat is called “scarification”. There are various ways to do it to bulk seeds; but for individual seeds you can use a file, knife, or sandpaper.

metal file

metal file

Here, I scratched seeds on a file.

scratching a seed on the file

scratched seed

I rubbed till the lighter colored interior showed through.

seed coat filed through

Seed coat filed through

I also nicked some seeds with a utility knife. I avoided the very tip of the seed, in case I might damage the embryo root, though seeds like this often protect their incipient root by embedding it somewhat back in the embryo.

Here is a scarified seed beginning to imbibe. This seed was both scratched and nicked. The flap towards the top is the nick.

seed beginning to imbibe

2015-11-25 09:19

The water absorption is a chain reaction. As the interior swells, it disrupts the seed coat from the inside, and allows still more water to enter.

Here is the same seed fully imbibed.

same seed fully imbibed

2015-11-25 12:05

The water absorption goes quickly after the seed coat is breached. Here, the seed has become fully imbibed after only a few hours. Many of the intact seeds were still dry inside after twenty-four hours soaking, and could have remained so indefinitely.

In order to closely observe the seeds, I put them in a standard germination test setup, rather than planting them in soil.

Here they are along the top of the folded, wet paper towel.

seeds on wet paper towel

I close the fold, and rolled this up on a chopstick.

seeds rolled up in wet paper towel

I held this, in light, at warm room temperature, about 80 degrees F.

seeds rolled in paper towel, standing in jar of water

2015-11-25 12:15

Within 48 hours, I had 100% germination.

ten mimosa seeds germinated

2015-11-27 09:01

close up of germinated seeds

close-up

This demonstrates that mimosa seeds’ germination requirement is primarily imbibation with water, and warm temperature. There is no inhibition by light, and no chilling requirement.

This explains why mimosa seldom volunteers in Portland. The time of year when temperatures are warm enough is also the driest weather. Seedlings that germinated in early summer would fail from drought later.