HOW often do you see trees and shrubs which have completely outgrown their site! This is a common problem, particularly when too near to buildings. There are several reasons why this happens.
Firstly it is quite difficult to imagine the ultimate size when planting initially. Secondly, the information on plant labels is not necessarily accurate, often the heights suggested are those which are estimated after 10 years rather than maturity – this is particularly relevant with the conifers and is one of my pet hates as I think it is very misleading. The third reason is often that after planting, there is no pruning carried out to restrict size and shape.
Many of the gardens I visit suffer from these problems, with trees growing over and under houses, filling gutters and stressing foundations and pipes. When I bought my place, there were two old cypresses and a chinese poplar planted a couple of metres from the house with roots growing under the slab big time, dropping leaves and needles on the roof and covering the northern aspect of the house, blocking the winter sun. Unfortunately, the chinese poplar was the most beautiful tree in the garden, perfect shaped and really well grown – if only it had been planted in a suitable place!
Where dense growing hedges or trees are planted for privacy or weather protection they must be trimmed from the start to grow in the right shape to achieve success. So often I see conifers that have not been trimmed and have grown into trees and outgrown their position.
Cypresses respond well to trimming and don’t need too much maintenance during the year, but like all hedges don’t wait until they have reached the desired height and width before you begin pruning.
Many of the good hedge species are in fact trees if left to their own devices, eg, photinias, laurels, cotoneasters, and pittosporums. Many of the natives need pruning to avoid unsightly, straggly specimens, whose lives could have be extended by some timely trimming.
Fortunately these days the nurserymen are breeding trees for suburban gardens and smaller spaces. These come, firstly, in the form of dwarfed varieties, usually grafted onto special rootstock to stop the vigour, used especially with fruiting varieties. The second method is to grow fastigated cultivars; these are much narrower than the usual form.
There are more and more fastigated trees coming on the market which is great for gardeners living in town. Not only do these shape trees take up much less space but they can still be planted close to boundaries and buildings without overhanging and taking over.
Pears are a good example of a species that has been very successfully manipulated, there are now several available with different sizes and shapes. A third method available in recent years is to buy grafted standards, some examples are moptops, weeping standards, and more recently some of the prunuses and crabapples are available with standardised trunks which is a great way to create the pleached look, “a hedge on stilts”.
These are very handy to add some height without having the garden below unusable to grow smaller plants and very handy to block out neighbours. Pleaching is used in Britain often and for those of you lucky enough to have visited Paris, the old city has the most beautiful pleached chestnuts lining the streets.
Traditionally, hornbeams and lindens were used most but there are lots of plants we could do this with. The Brits also grow deciduous hedges, using beeches, maples, hornbeams, berberis and roses just to name a few. With the new season deciduous trees, shrubs and roses now in stock you you might like to visit your local nursery to see what is available.
Happy gardening,
Jude
