Pruning and Training Soft Fruit Plants
PRUNING AND TRAINING
Although you can produce fruit crops without(wild plants, after all, manage tolerably well), there’s no doubt that an unpruned plant will soon become a tangle of growth, its cropping efficiency will decline and it will look far less attractive.
Pruning isn’t complicated, although the individual requirements of different types of soft fruit vary considerably: autumn-fruiting primocane raspberries, for example, should simply be cut completely to level in the early part of the year, whereas an established cordon-trained gooseberry must have its side-shoots shortened twice a season. I’ve given full information under the individual entries, but there is an underlying principle and logic to all of it.
The essence of pruning a fruit plant is to remove parts either that have passed their time of peak contribution to the plant’s fruiting efficiency, or that will never play a useful part in promoting it. Left on the plant, they will divert valuable food and water resources away from the fruit and then, in time, as they become moribund, serve to encourage the establishment of pests and diseases. The main reason that different pruning systems are used for different types of plant is that theirand, subsequently, their fruit are borne in varying ways. The primocane raspberry is the extreme example of a plant that bears its flowers on shoots produced during the current year. 1T is precisely because it takes until the end of the season for them to have sufficient time to mature that they are autumn- and not summer-fruiting. But the old fruited canes do afford a small degree of frost protection during the winter, so don’t cut them out straight away, but wait until the late winter or early spring when you should then prune them all right down to soil level.
By contrast, a grapevine also bears its flowers and fruits on the current season’s shoots, but with the significant difference that these shoots are themselves borne on an established older woody framework. Thus, whilst the fruited shoots are also cut out completely in late winter, they are cut, not back to soil level but back to the junction with the main stem, or rod as it is called.
There are other variations: for example, blackcurrants bear the most abundant fruit on one-year-old wood with some on two and three year-old wood but little on wood older than that. By contrast, red and white currants and gooseberries fruit on short spurs borne on old wood. In all instances, the pruning suggested takes account of these different fruiting habits.
Where there is a choice of shoots to cut out, always cut the oldest or the most misplaced first. The oldest will generally be thicker and tougher; and by misplaced, I mean such examples as blackcurrant branches that hang below the horizontal and would, therefore, be dragged to the soil with the weight of fruit, or raspberry canes that arise 30cm (12 in) or more from the main row.
TOOLS FOR PRUNING
You won’t prune neatly and well without suitable tools. For soft fruit canes and bushes, two should suffice: secateurs and loppers. Because you will be pruning very few soft young shoots (and even these are generally better nipped out with finger and thumb) but a great deal of harder, woodier stems, single-bladed anvil pattern secateurs are better than the scissor or by-pass type. And anvil-style long-handled loppers will enable you to cut through thicker branches — old blackcurrant stems that need to be cut out at soil level, for instance. As a general rule, even with the largest model of anvil secateurs, you shouldn’t try cutting stems thicker than approximately 2cm (3/4in), whereas most good loppers will deal with stems up to about 3.2cm (1-1/4in) thick.
I like to think of training as a means of keeping a plant in a neat and manageable state so that its pruning can be performed satisfactorily. Indeed, in the early stages, the pruning itself is often described as ‘formative’ and is done with the purpose of training a plant for the long-term. Strictly, training means persuading a plant to grow in a way and direction that is of your choosing.
SUPPORT FOR PLANTS
Many types of soft fruit must be trained against some form of support, for their stems are too weak to support themselves properly when free-standing. The climbing fruits, grapes and Kiwi fruits are the obvious examples of this but the pliable-caned blackberries and their relatives would also be reduced to a mound of tangled growth such as those produced by their wild version, the bramble, if wires were not used to support them. And while wild raspberries are short, rather stiff-stemmed plants, most of the cultivated varieties have tall, rather flexible canes that are easily damaged by strong winds.
Generally, the bush fruits (currants and gooseberries) need no physical support when grown in the conventional manner. But they can very usefully be trained in cordon form, where one or more vertical shoots are persuaded to grow vertically, the remainder being cut out. And in this form, the single tall shoot will, indeed, be unstable unless it is tied to canes and wires. I’ve dealt at some length with the way to construct wire support systems in my account of raspberry growing.
But while a free-standing bush needs no support, it still requires some training if it is to be cropped efficiently. Some of the shoots must be cut out at an early stage to prevent overcrowding and those that remain should be chosen carefully to produce a goblet-shaped plant with a fairly hollow central area. The effort needed is relatively little but a well and carefully trained bush will crop more effectively through being easier to prune and manage. And to my eye at least, a well trained soft fruit garden will always be so much more pleasing to look at and work in.