Heavenly bamboo, or simply ‘nandina’, is one of those many plants that almost never performs like it should. The intricately lacy foliage is so appealing while plants are young, and changes color with the seasons. The red berries can be comparable to those of holly. Unfortunately, healthy plants grow, and then ultimately get shorn into globs of disfigured leaves and stems.
The same abuse afflicts Oregon grape (mahonia), mock orange (philadelphus), forsythia, lilac, abelia and all sorts of shrubby plants that really should be pruned with more discretion. Their deteriorating older stems should be pruned to the ground as new stems grow up from the roots to replace them. It is actually not as complicated as it seems.
This pruning process, known as ‘alternating canes’, prunes the plants from below. It is a standard pruning technique for maximizing production of blackberries, raspberries and elderberries. It is similar to grooming old stalks from bamboo and giant reed, even if it does not prevent them from spreading laterally.
The deteriorating older stems, or ‘canes’, are easy to distinguish from newer growth. Old canes of Heavenly bamboo and Oregon grape become heavy on top, and flop away from the rest of the foliage. Old canes of mock orange and lilac get gnarled and less prolific with bloom. Aging abelia and forsythia canes become thickets of crowded twigs.
The newer stems are likely a bit lower, but are not so overgrown. Since the foliage is not so crowded, it is displayed on the stems better. Their blooms or berries are more abundant. By the time new growth becomes old growth, there will be more newer growth right below it. In fact, the regular removal of aging canes stimulates growth of new canes.
This is the time to prune Heavenly bamboo and Oregon grape, just because the oldest foliage is as bad as it will get after the warmth of summer. Mock orange, forsythia and lilac should get pruned while dormant through winter, but are commonly pruned just after they finish bloom early in spring. Abelia should probably wait until spring because new growth can look sad through winter.
This does not seem like such a mild climate when it is difficult to distinguish between the time and the temperature on a local bank clock tower. You know; when punctuation is the only difference between four minutes past one, and one hundred four degrees. Fortunately, like mild frost in winter, hot weather does not happen too often, which is why this climate really is milder than most.
How can a professional ‘gardener’ leave such a stub on the little California black oak in Felton Covered Bridge Park. It is not as if it is high in the canopy of a large tree, and out of reach to an arborist. This one is right at eye level, exactly where someone getting out of a car parked in the adjacent parking space would run into it. The entire tree needs some major corrective pruning, which would include the removal of significant limbs and portions of the canopy, but that is only because of years of neglect, and is another story. Right now, we are focusing on the eye-level stub.
Those of us with ‘maintenance gardeners’ are likely aware of how rare it is to find someone who knows how to maintain hedges properly. It seemed so simple years ago. Several identical plants could simply be planted in a row, and then somewhat regularly shorn for confinement to a prescribed space. They were not allowed to exceed a specific height or width for long between shearing.
Wildlife and domestic animals seem to follow me everywhere I go. When Brent and I lived in the dorms at Cal Poly, our room was known as the Jungle Room, not only because of all the greenery, but also because every little bird that got knocked out while trying to fly through the big windows at the dining room was brought to our room to recuperate. A baby squirrel that weaseled into my jacket while I was out collecting insects for an entomology class lived with us for a while. There were two baby ducks that need a bit more explaining.
There is no doubt that frost will return next autumn. It does that every year. Right now, we are more concerned that is should not return prior to that. It is now safe to plant plants that are sensitive to frost. Even if the weather were to somehow get cold enough to necessitate protection of frost sensitive plants, it will not be severely cold, and it will not last long. It is best to start now than to delay.
Pollarding and coppicing are bad words to most American arborists. These extreme pruning techniques are considered to be synonymous with topping. Yet, both have been around for centuries, and have actually kept some trees alive and productive significantly longer than they would naturally live.
Winter is the best time for major pruning of most plants. They do not mind it so much while they are dormant. However, there are exceptions. Winter pruning might be a bit too early for a few plants that are grown for their late winter or early spring bloom. It is best to wait until immediately after bloom to prune or trim flowering cherry, flowering plum, flowering crabapple and flowering quince.
Tony Tomeo 