Q: May I have some details on pruning pine trees? We have some in the yard, and we want to keep them as part of the landscape. We don’t want them to grow into hundred-foot giants. What is it that we must do with the candles?
A: You must have Austrian, Mugo, Scotch or similar short and bushy pines, not tall Ponderosa pines. Here are four suggestions from an arborist who has had a long career in shaping trees and teaching students how to do so.
The first way to prune pines is to cut off half the length of all the candles, the new light green growth, in spring. That will cause branching and will lead to shorter, thicker growth. If you want to create the formal style called cloud pruning, this is how to begin.
A second way to shape a pine is by cutting some candles and leaving others. The candles which remain will not branch. The result will be a tree which grows unevenly and looks natural, instead of one with a formal, symmetrical shape.
On a larger pine, instead of cutting candles, prune branches back to secondary branches within the canopy. This will immediately reduce the space occupied by the tree. When removing branches, be sure to cut to the whorls where branches originate. A branch cut to bare wood will die.
The fourth pruning possibility is to remove branches in the interior. This will cause the tree to look older than its years. For this kind of pruning, start at the top and gradually work down, making small cuts. The process will take several years. “Starting at the top” means with the uppermost side branches, not with the leader. (The leader is the upright tip of a conifer.) NEVER cut off a leader. Conifers will be misshapen or even killed as a result.
Q: I am planning to switch my vegetable garden to the no-till system this year. That will mean many semi-permanent paths. If I do not till the paths to keep weeds down, what do you recommend?
A: Since those narrow strips of ground will see a lot of foot traffic, it is only sensible to protect their soil structure. The smaller the soil particles, the more protection is needed. Clay is the extreme example of small particles; when wet, it turns to gumbo which sticks to shoes in great clods. Some gardeners with clay soil lay down boards and never step off them. Whatever your soil type, good drainage from paths as well as vegetable beds will maximize the water available to the vegetable roots.
I have tried a variety of path surfaces between my vegetable beds. Finally, I voted for the ones that are easiest to maintain. Wood chips make a good surface, although they do break down gradually. Every year I see places where chips are becoming less visible and need a fresh addition.
After a few years some of my paths started turning themselves into strips of Kentucky bluegrass, seeded from the lawn. The grass is easy to mow. Its main disadvantage is that its stolons crawl into the edges of the vegetable beds. Grass plants must be dug out at least once a year, since they find the rich soil of the beds their preferred place to live. Occasional weeds find a foothold in a grass path. With a soil knife, I dig out from the paths the same weeds I remove from the lawn.
I would not recommend gravel paths. Besides being uncomfortable to kneel on, the gravel soon is infiltrated by dirt. The paths turn into either weed beds or mud.
Also I do not recommend landscape cloth. I tried it, as well as black plastic, early in the sequence of making raised beds. The problem was the same as with black plastic anywhere in the landscape. Covered with a thin layer of chips for the sake of appearance, the plastic worked well for two years. Then quackgrass rooted itself from underneath and weed seeds rooted themselves from above. Landscape cloth has ready made holes which weed roots take advantage of. Impermeable plastic soon is riddled with tiny holes. The resulting weed strip has to be cut out, inch by inch.
Some gardeners create more permanent paths of pavers or bricks. They certainly give the garden a more formal appearance. The formality also is costly.
Q: I understand the issue about the amount of plastic used in gardens, but, realistically, what can I do? Every plant I buy comes in a plastic pot with a plastic label.
A: I agree. Plastic use in the garden is not going to disappear this year or next. Since the amount of plastic used makes most gardeners uncomfortable, we can nibble away at the problem as individuals. Even if each of us finds only one substitute for plastic with just one plant, the enormous number of gardeners in this country will add up to significant change.
Some reasonable ways to decrease plastic use are: Reuse existing pots and labels as much as possible. If you are not going to use pots again, take them to a local nursery. They will be able to reuse anything except multi-packs for seedlings.
Rather than buying plastic labels, use wooden craft sticks or strips cut from non-recyclable plastic containers.
If you start your own seedlings, grow them in paper modules, toilet tissue rolls, newspaper pots, or soil blocks. Besides avoiding plastic, these plantable containers will make stronger, healthier seedling plants because roots are never disturbed.
HOUSE PLANT PRUNING
I promised a further report on my Aralia marginata. I had allowed it to become a three-foot tree with a bare trunk, its only foliage a tuft of variegated leaves at the top of the trunk. Poor thing, it was an ugly specimen which needed help to regain its former beauty. I made a cutting of the top, taking off the entire leaf cluster. I then removed the leaves from the bottom inch of the cluster, dipped the base in rooting hormone, stuck it in a two-inch pot of damp soil, and sealed it in a clear plastic bag.
Also, I gave the bare trunk a chance to see if it could grow new leaves. I cut off the top half, deciding that a trunk 12 or 15 inches tall would look appropriate. Otherwise, I left the trunk undisturbed to eliminate further stress. I continued to water it enough to keep the soil damp. I did not move the pot, except to turn it every day, while I looked for any hopeful sign.
I have now been rewarded. New roots on the top cutting were coming out the drain holes in the pot. I opened the bag for a couple of days to ease the transition to room air, then moved the cutting to a six-inch pot. Meanwhile, that bare trunk has begun to grow. At the moment it has a reddish bud on the cut edge, and three tiny branches sprouting from the top inch of trunk. The longest branch is only an inch, but it already has a miniscule leaf.
Aren’t plants amazing?