Caring for Shrubs
Caring for shrubs
One of the nicest things about shrubs is the very small amount of regular aftercare they require from the gardener.
every springtime — which means adding a layer of material to the surface of the soil round the plant — is virtually all that is needed, apart from pruning, and occasional feeding with a proprietary .
Theshould be several inches thick, placed around the plant in an area that will cover the probable spread of the roots. In practice this is at least equal to the spread of the branches, but if this is rather large, it need not be strictly adhered to. Garden compost, , , spent hops, mushroom compost and very well-rotted can all be used, and will help to improve the structure and of the soil and supply it with food, which is generally washed into the soil by rain. Be careful not to get the mulch too close to the base of the stems as it could provide a cosy home for mice and voles, who will chew the bark of the shrub and so kill it.
The addition, occasionally (say every two or three years) of what is known as a concentrated or ‘artificial’ fertiliser, which contains the most necessary of the chemicals essential for the plant’s diet, can be helpful in producing a first-class plant, particularly where it is growing on soil which contains a good deal of sand. Water drains through such soil quickly, and as the chemicals are dissolved in the water, naturally the plant foods are also lost. (Mulches on these soils act as sponges and help to retain water and food.) Ifare to be given, the spring is the time to do it. Bonemeal may be used in the autumn.
In some of the descriptions of shrubs it is mentioned that they require an acid soil; if an attempt is made to grow them in alkaline soils the leaves turn yellow and growth stops unless special steps are taken. Most people grow only those shrubs which are suitable to their soil, but sometimes they consider special treatment is worth while. A simple soil tester will show if the soil is alkaline, and if it is, lime-hating shrubs must be started off in a pocket of lime-free soil. This of itself is not enough, and the shrub must be watered once or twice a year, according to the degree ofof the soil, with a solution of a proprietary chelate or Sequestrene compound. This can, however, be quite expensive over the course of years.
Many shrubs, if unpruned, rapidly deteriorate into flowerless, straggly plants, full of leaf, with crowded stems and lots of ‘birds’ nests’. Pruning encourages the production of new shoots which will have flowers on them and, when done in conjunction with regular and occasional feeding, will produce healthy attractive plants. The removal of crossing shoots, diseased shoots or those that are too close, can be carried out; this is important as it lets air into the centre of the bush, and also light which ripens the flowering buds and ensures a better display the following year. Broken branches should be removed by cutting cleanly back to a suitable junction. If the branch is very big, the wound made by cutting should be painted with a sealing compound or grafting wax, to prevent the entry of diseases.
The explanation of one or two terms used in pruning might be useful. ‘Cutting back to a bud’ means cutting off the shoot with a clean cut in such a way that the cut is made just above the part of the stalk where a leaf or a pair of leaves grows out of the stem. Between the leaf stalk and the stem will often be found a small bud which may be a flower bud, or a vegetative bud – the sort of bud which grows into another shoot. The cut is made above this bud, taking care neither to damage nor to remove it. It is important to make a clean cut.
‘Tipping’ means cutting off the young growing shoot, removing only about 2 inches, possibly 3 inches, from the top of the shoot. Cutting ‘hard back’ means removing most of a shoot, about three-quarters of it; or hard back may mean almost to ground level.
Pruning ‘lightly’, or ‘thinning’ means either removing about a quarter of each new shoot all over the bush, or removing an occasional shoot entirely, simply to prevent overcrowding.
For most pruning, a pair of secateurs is all that is needed, either with a blade cutting down on to an anvil, or the scissor type. A knife is also sometimes useful, and a pair of lopping shears or branch cutters for removal of rather large, tough shoots.
Time to prune
The majority of shrubs fall into two classes so far as pruning is concerned: those which flower from July onwards and are pruned in the spring in March, and those which flower from the spring until the end of June and are pruned immediately after the flowers die.
The late-flowering shrubs are pruned in March when the plant is starting into growth, to stimulate the production of lots of new shoots which will carry flowers later in the season. The spring flowerers, pruned immediately after flowering, should normally have the old flowering shoots cut off, except where the fruits are attractive. They should either be cut back to strong new shoots which will already be growing to take their place or, if these have not yet started, to within an inch or two above the base of the old flowering shoot; this may be to ground level.
Where special pruning is required this is mentioned with the description of the shrub concerned. Some may only require the removal of the dead flowerheads as with rhododendrons; straggling shoots may need tidying.
With judicious pruning, not necessarily every year, it is possible to produce the maximum of flower and yet preserve or enhance the natural habit of the shrub.