Q: Just a question about pyramid cedars. We have several and many are overly tall and split from snow. How severely can I prune these back and keep them live?
Tina Manke,
A: Lots of people had the same problem with pyramid cedars this last winter.
Its really best to avoid pruning if you can because cedars dont readily re-shoot from older wood. That means a bare patch stays bare unless you can fasten other branches to cover the gap.
The splitting can be dealt with by tying the branches closer to the trunk with wire or tough string. Sometimes you need to fasten branches to each other to recapture the original narrow outline. The tying will be visible at first but new growth will cover it after a while.
If you feel you must cut back some of the overly tall branches, its best to remove the entire branch back to the trunk. But this should only be done if nearby branches can be tied-in to cover the gap. If you shorten only part of a long branch, chances are it will look really ugly and never make enough growth to improve its appearance.
Q: I know grapes like well-drained, alkaline soil. Do they need fertilizer? I see that professionals prune their grapes back very harshly to one main stem each year.
My three plants, a small black (Niagara?), a pink and a white were bought with three main stems two or three years ago and I left them like that. Should I spray routinely against molds?
Jeremy Greenfield
A: Grapes need very little fertilizer. High-nitrogen fertilizer is especially bad for them, causing the growth to become very leafy and fruiting to be inhibited.
Some gardeners like to use a fertilizer high in phosphorous with moderate potash. But other gardeners, especially organic ones prefer to mulch grapes with two centimetres of well-rotted compost each year.
Id suggest you start out with the compost method. Its easier and compost is more likely to contain the wide range of micro-organisms that produce healthy soil.
Its quite possible to grow grapes for years without using sprays. The harsh pruning you mention opens up the vines to light and air and makes fungal problems less likely. The more leaves shade each other and the fruit, the more wetness lingers in the vine and attracts mold, mildew and rot problems.
Routine spraying may not be necessary if your pruning is adequate.
Sites that cause problems for grapes include north slopes, frost-pockets, low-lying areas and places where large trees or buildings keep grapevines in shade for part of the day.
The more organic your vines can be, the better. Sprays always kill beneficial organisms as well as the harmful ones.
Q: Is it possible for camellias or rhododendrons to re-seed themselves? I have several plants growing in various places in the garden and they have the same type of leaf that a camellia does, but I havent a clue as to what they are. They havent bloomed yet.
Pat MacAllister,
Langley
A: Yes, camellias and rhododendrons can seed themselves. But the most typical things with similar leaves that volunteer around neighbourhoods are English laurel, Cherry Laurel and sometimes Daphne laureola. All are evergreen and have a bad reputation for invasiveness.
Anne Marrison is happy to answer garden questions. Send them to [email protected].
