by Terry Davis
Root Growth and Internode Spacing
I had heard that the longer a root grows in a season, the longer the internodes will be. This is especially true for tridents, which may lap the pot several times a year. I was looking over a recent shipment of maples and noticed that the internodes on the lower part of the tree (as evidenced by the growth scars) are much more widely spaced than the buds on the tips of the newer branches. I think this is because early on, the tree was putting a lot of energy into growing roots. Later on, the pot is filling with roots, so maybe root growth has slackened off, so the internodes get closer. What this means is that you need to work at getting the finest, densest root mop you can, which you get by re-potting often. I have mentioned Ted Matson’s trick of root pruning tridents just after the buds pop, to set the tree back a bit. This promotes a dense mop of short, fine feeder roots, and slows the Spring “Sproing” which in turn slows down top growth. Et voila: two birds with one stone! I don’t think I would try this with a tree which isn’t incredibly strong, which is about everything that isn’t a trident!
I suspect that, if you're potting the plant in a larger pot, it might make sense to do it after the Spring growth has finished. I know azaleas, when moved to big a pot, will spend a whole lot of time just growing roots, and not getting bigger, so move them up gradually. I put some in the ground and they just sat there, relative to the ones in the pots.
fI you are grafting, the rootstock should be as moppy as possible. Here’s how you get there: put rooted cuttings or hatch seedlings in 2” rose pots. I have a friend in the wholesale nursery business in FL who cut the bottoms off the pots with a band saw, then packed them into wooden frames with screen wire bottoms. When a root hits the air, tip growth stops. This goes not only for your grafting root stock, but is also great for getting better root systems on cuttings and seedlings. Look Ma, no taproot! They used to make larger “Rootmaker” pots, with perforated sides. I am told they are still available, but my impression is that the kick-start for the smaller stock may be all you really need. I suspect you could do the same with 4” square pots, too. In fact, I would aim that way.
Reinforcing Air Layers
I am sitting here, looking at this flock of new maples, and thinking it is going to be a berserker season for the air layers this Spring. I don’t know if you have had the experience, but air layers of smaller stems (say, pencil size) tend to break off, and the layer is kaput. I was thinking of what I could put up against the stem, in the way of a brace, to keep this from happening. I am not so sure a chopstick would be all that good an idea, as it might get cruddy and infect the works, but maybe it will work. I think maybe my best bet would be to run a copper wire, worked to stiffen it, up a plastic soda straw and strap this against the stem. I tried layering some bigger branches of a wild plum in my yard, and these were no narrow stems, but 1/2-3/4” branches. Since they were blowing in the wind, sticking out horizontally, and getting pounced upon by squirrels, they all broke off. So maybe reinforcement would be a good idea there too.
‘Tis the Season When Things Improve
Spring re-potting is upon us like a cheap coat! And this is the time of the year, not only when the wannabe’s get their first bonsai pots, but that maple that you planted to the wrong side of the pot gets put in its proper place. I don’t know about you, but this happens way too often to me. Sometimes it is because you have big roots you couldn’t take off yet, and you have to have put it that way. And sometimes it’s because the planting position with the proper balance was not what you thought it was the first time around, and now you’ve had a year to think it over and realized you could do better (amazing how good it feels when a mistake gets made right)! Sometimes you just didn’t quite have the right pot, or got conservative at the first potting. (Leave us face it: sometimes I move things into bonsai pots, any old bonsai pots, just so I will start paying more attention to them. (Don’t get snarky, now! This is the voice of experience speaking))! And sometimes (maybe a lot of the times), it may have been because I was freezing my kiester off re-potting in the Minnesnowta cold, and made a decision too quickly! Working furiously while periodically running back into the house to thaw my fingers out at the tap. Things pop in the (cold) greenhouse long before the snow is gone. Up here among God’s Frozen People, we call that “pushing Spring”! The same phenomenon that drives many to break out the flip -flops when the temp hits 50°.
And, woohoo! This is a chance to finally get rid of @#$%^&* persistent weeds! They are the ones with the white roots.
Staking is for Vampires
Seems like a suitable time to remind the beginners that the object of chopsticking is to work the soil into place, not to murderize the living daylights out of the roots. So many People I have seen just stabbing the heck out of their plants. You put the stick in, and you WIGGLE IT back and forth radially! Not sideways. When you first put the plant in the pot, put a mound of soil in first and gently work the plant into it some so you aren’t mashing roots into the bottom of the pot. It helps, once soil ahs been poured on, to give the pot a few bumps with your fist or a gentle thump on a soft surface to settle the soil.
When I am potting nursery stock, I generally remove the bottom of the soil ball and give the whole thing a few hard bumps on the ground to remove any loose dirt.
And About that Other Chopsticking Problem:
You use some means to remove the top of the soil from a stock plant until you find the surface roots. But it does you little good to find them and destroy them at the same time. I prefer a gentle spray of water, and the best time to find the surface roots is well ahead of the workshop time, if you already have the plant. You are paying for your teacher’s time, and searching for surface roots during a workshop (unless you just got handed the plant) is a waste of time and money.
Terry’s Law of Re-potting
It always takes twice as much soil as you thought it would!