Planting | Pruning | Weed control
For easy maintenance, shrubs are next best after trees. Shrubs can be used in small gardens to fill space in the same way that trees can be used in large gardens. Many of them are fast-growing and quickly fill a considerable area. A piece of ground planted with shrubs has a much lower maintenance requirement than a similar area of lawn. Therefore, the conversion of part of the garden area to accommodate shrubs reduces effort. Many shrubs clothe themselves with foliage down to ground level, which increases their competitive ability over non-woody weeds.
Weigela florida 'Variegata'
Most shrubs are grown in containers and sold as container-grown stock with their full root system intact. This means that they are easy to get established. When planted during the late autumn or early spring, they are unlikely to need any subsequent watering, except possibly during drought spells. This is a considerable saving of effort.
Because they have their full root system, container-grown shrubs can be planted during the growing season. However, this means losing the advantage of reduced effort because they must be kept watered until well established.
Shrubs can be planted through dead sod, as described for trees, but each shrub must have a proper planting hole dug out. This should be 10 to 20 centimetres wider all round than the rootball from the pot. Loosen the soil over a wide area, then take out the planting hole in the centre and plant up.
Shrubs vary greatly in their requirement for pruning; some kinds rarely if ever need pruning, some need occasional thinning to keep them neat. However, no shrub need necessarily be pruned as a matter of course. Where there is space, they can be let grow as they please.
However, space is a limiting factor in most gardens and the main reason for pruning shrubs is to keep them within bounds. If you prune out roughly the amount of growth the plant puts on each year, then it will stay about the same size, or only slowly get bigger.
No pruning is necessary at all for the first five or six years, or until the shrub is flowering well, if it is a flowering kind. Then, remove about one in five of the plant’s branches each year, choosing the oldest ones to go. Most shrubs flower best on young growth so this will not upset flowering.
Do not remove part of all the branches because this interferes with flowering. Never trim a shrub with a hedge-clippers unless it has fine foliage like that of broom, heather or lavender. The principle is to thin out the shoots, not shorten them all back.
Some shrubs like rhododendrons, magnolias, pieris, enkianthus, and most evergreens are best not pruned at all. Pruning applies mainly to bushy, twiggy shrubs that produce a lot of new growth each year, particularly from ground level or near it. Choose shrubs that rarely, if ever, need pruning, and give them adequate space. This approach can reduce, or remove, the necessity to prune shrubs at all.
Although shrubs are competitive against weeds, in most cases they are not as competitive as trees. Whereas trees only need a high level of weed control for the first five or six years after planting, there will be a need to maintain proper weed control throughout the life of a shrub planting.
Weeds selected killed among young shrubs
Hoeing is a good method of weed control among young shrubs. It is not time-consuming if the ground is completely free of perennial weeds before planting, and if the seedling weeds are controlled before they reach 5 centimetres.
Mulching can provide a major saving of effort as an alternative to hoeing. Bark mulch is the best choice because it is free of weed seeds. It must be laid on weed-free soil to an even depth of 6-8 centimetres. Grass mowings are very effective too, but not deeper than 5 centimetres at a time. Garden compost is not really suitable for this purpose because it contains weed seeds.
It will be necessary to remove weeds that manage to establish themselves on the mulch, either by pulling or by directed spray of Roundup. If willow herb builds up as it is resistant to Roundup, use Weedol or Bio Weedfree.
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