Expert Tips for Pruning Fruit Trees
Pruning Fruit Trees
So far I have said nothing about the tools to use forfruit trees. These consist essentially of a pair of secateurs, short or long handled depending upon the job, a saw and a sharp knife, preferably a hooked pruning knife. There is the type of secateurs where the blade cuts onto a soft metal anvil simulating the knife blade on the ball of the thumb and is, incidentally, a lot less painful. Then there is the type with scissor blades where the cutting blades cross and have a guillotine effect. although cheap secateurs are often an attraction, they have a limited use. They may be good enough for small jobs but very soon the blades become strained and you might as well use a pair of pliers to crush the shoots to be removed.
Many of the growths which are pruned away are hollow or contain only soft pith which offers little or no resistance to strained, ill fitting, poorly designed or badly sharpened secateurs. These bruise and damage the branch with the result that the mangled wood dies and allowsof disease to breed in it which may eventually even kill the plant. This happens more often with than most people could believe possible. Apropos of this, if salesmen demonstrate to you showing how their secateurs can cut through hazel twigs thicker than your thumb, ask to see them cutting something which is hollow. Any sort of secateurs will cut through solid wood but not all will stand up to the test of the hollow tube.
The saw is needed for pruning fruit trees, to cut through any growth more than 3/4 inch in diameter and, preferably, a specially designed pruning saw should be used. In any case, a saw to cut green wood should have sufficient ‘set’ to provide clearance and all cuts should be made on the underside first, cutting in as far as is possible before the weight of the branch nips the saw blade. The object of this is to prevent tearing when the branch falls. A clean pared surface heals and calluses over much more quickly than a ragged edge where the bark has been chewed about by the teeth of the saw, and this is where the sharp knife comes into the picture. The surface of the wood should be pared and particular attention should be paid to the bark, beneath which is the cambium layer. This consists of an active living and growing group of cells which will continue to grow and in time completely enclose the severed portion of the branch.
As active growth only takes place in the cambium layer, the central portion of the severed branch must be regarded as dead wood. In fact the branch will begin to decay very soon unless protected, and cause a hollow to form which may penetrate eventually right down the centre of the tree. Personally, I have found nothing better than either grey lead priming paint or aluminium-based priming paint to cover these wounds. Gloss paints often form a skin which eventually peels off and does little towards the permanent protection of the exposed wood. Painting over the cut surfaces is not just to make them look tidy, but prevents the entry of water and funguswhich set up the rot.
The pruning or the lopping off of large limbs, be they from fruit trees, ornamental or even forest trees, is best done during a period of dormancy. In the case of conifers this should be just before active growth commences in early spring. In spite of this, large wounds may start to weep profusely and the sap will even drip out like water from a leaky tap. Nine times out of ten this corrects itself and does no harm, even with subjects such as. Speaking from my own experience, the only harm done that I have ever seen, even after copious bleeding, is that the sugary sap of some trees congeals on the cut surface and fungus spores breed in this sweet jelly-like substance. Under these conditions when bleeding has actually stopped, the solidified sap can be washed off with detergent and the wound painted with disinfectant solution such as one part Jeyes fluid to twenty parts water.
Cuts of any kind are best made at an angle for two reasons. one is are that it is easier to cut obliquely across the grain than at right angles to it. The other is that if the cut is inclined so that the face is pointing downwards, then the rain will run off. Never cut so that the sloping face is uppermost, because if the angle is acute then water can collect. Young wood, particularly, has a tiny core of pith which decays and leaves a channel for spore-laden water to percolate.
When pruning fruit trees of stoned fruits, such as plums and cherries, be they fruiting or ornamental, special care has to be taken. Even with the greatest care and skill in the world the removal of large branches may result in disaster. Along with magnolias and other shrubs which dislike pruning, plums and cherries should never be allowed to reach a stage where large branches have to be removed. although very often when you inherit trees like this it can be a problem and you hesitate to do anything about it until it reaches the stage when massive surgical operations have to be undertaken.
I doubt very much whether the single operation of pruning fruit trees adds a pound of fruit in terms of quantity, which inevitably raises the question, ‘Why bother? The answer, of course, is that it materially improves quality and improves the general health and well being of the plant, as well as lengthening its life. Pruning to me is an art and has no end in itself but the successful training with all its benefits which result from good pruning.
Improved Fruiting After Pruning
Most people can argue that they have large old trees in their gardens which fruit regularly, and never receive the slightest attention, either from knife or saw. This is perfectly true, but these trees have reached the stage of stability where the actual fruiting acts in the same way as early pruning. The pruning is a method of early training and formation. When the tree reaches a certain maturity it settles down and becomes self regulating.
There are, however, a few basic principles of pruning fruit trees which, if mastered, would enable you to produce bigger and better fruit as well as increasing the fruitful life of the subjects. First of all, forget all you have ever read about ring barking, root pruning, driving in nails and all the weird and wonderful things that are supposed to make unfruitful trees bear fruit. In many cases the results would be far better if the trees were left alone. For a start, hacking a tree about doesn’t make it fruit any better. Cutting off large branches very often does no more than produce scores and scores of little whippy growths which are no good to anyone and do more harm than good to the tree.
A very young tree is like a young child or animal which needs training. The way a tree is pruned depends a great deal on the type of training decided in the nursery, be it standard, bush, fan, espalier or any one of the many different forms. The normal, and perhaps most useful, type of apple tree for example, is the bush. When well grown this is roughly like a wine glass in outline and without central growth. A pyramid, on the other hand, is a tree with a central growth with branches coming out all the way round, roughly like a child’s idea of a Christmas tree. So, obviously, if the centre was taken out of a pyramid-trained tree then it would become a bush because the secondary growths would come up to replace the central stem. For all practical purposes, whether you are training a young tree or renovating a very old one, it is important to see that the branches are well spaced and that air and light can reach the centre of the tree.
When a tree is very old and has been allowed to grow its own sweet way, then invariably branches will cross and, in crossing, often rub against one another. Whether it is an apple, pear or plum of any age, this must be eliminated or prevented. So as soon as the leaves have fallen off your trees have a look at the branches, get under them if they’re big, look up through them and see where they are crossing and rubbing. This rubbing causes wounds into which disease penetrates; cankers and all sorts of troubles start from here. Most old trees can do with at least a third of the wood cutting out to let in air and light. When pruning fruit trees, all cuts should be made cleanly and any cut over 1/2 inch thick should have the edges pared with a sharp knife after using a saw.
Staking Fruit Trees
Although at first sight, planting has little to do with pruning, it is nevertheless very important to see that for the first year or two of its life, the tree is adequately staked. In my experience where I have cut, carted, sharpened, and driven in, literally hundreds of thousands of stakes and in all cases two stakes per tree were used with a cross bar to which the tree was tied. This is certainly an ideal method in an orchard, as it allows the driving in of stakes without risk of damage to the head of the tree by the mallet and the stakes may be placed farther away from the roots which at that time will be small. Of later years, I have experimented with the use of short stakes and find that these work very satisfactorily, not only for fruit trees but for ornamentals too. The stakes are about 3 1/2 ft long, pointed at one end and driven into the ground at least 18 inches, so that they are perfectly solid and rigid. A pad of either cloth, rubber or feIt is placed between the stake and the trunk as a protection against chafing. The bottom part of the trunk is then secured so that there is no movement of the roots.
I got this idea from an old Scottish friend of mine, who had assured himself that if the trunk of a tree was allowed to flex itself and bend, it developed more elasticity than if tied rigidly to a stake. It certainly prevented the head being snapped off at or just above the tie. There is a danger, of course, that where winds blow consistently from the same direction the tree will develop a lean unless a taller stake is used. The important thing is not the top but the roots, for if these waggle about the tree takes a long time to settle down. Constant breaking of the roots will cause suckering, particularly with stone fruits such as ornamental cherries, plums and almonds.
Rejuvenating Old Fruit Frees
To wade into an old fruit tree or bush with saw and secateurs is not the answer to this problem as, nine times out of ten, the hard cutting will only produce a mass of young brash growth. This is especially true of apples and gooseberries. If the fruit of an old and neglected apple tree is worthless, inferior or it is one of those semi-precious trees grown from a pip which has never fruited it pays to cut the trunk hard back and crown graft with a good variety. If the old tree forks at a height of under 5 ft from the ground, the cuts may be made through the thick branches about 9 in from the crotch. Crown grafting, which may be done in March or April, need not deter even the novice, as it is the easiest and most certain of all the forms of grafting.
If the variety is good, but the tree has got completely out of hand, it may be cut down as above which will encourage dormant buds to sprout. Then it is only a matter of rubbing out the unwanted shoots and keeping the best placed ones to form a new framework. Many old trees, however, do not require such drastic treatment and only need the cutting out of branches which cross the centre. A particular problem which arises here is the very thick branch which has crossed from one side of the tree to furnish almost half the opposite side. In this case, trim off any smaller branches arising from it which are choking the centre. This cleaning out of centres cannot be over emphasised. This job is essential even if nothing else in the way of pruning is done. Thick branches carrying no leafy twigs can fold over each other in the centre as much as they like provided they do not rub or chafe, it is the host of small ones cluttering up the middle that matters.
When pruning fruit trees such as plum trees are best cut back before or soon after leaf fall, and if very thick branches have to be removed, I prefer, where possible, to do this over a period of two years. This not only reduces shock which may cause death, but reduces the resurgence of growth which often takes place producing masses of wand-like branches with widely-spaced buds, more suitable for walking sticks than fruiting wood.
Neglected gooseberry bushes should be tackled boldly and the whole centre removed, but if the bush is not growing on a leg it is far better to strike cuttings to make new bushes and scrap the old ones. Bushes which have been formed by division or growing up from a ‘stool’ or a cluster of growths from the ground are nothing but a nuisance, as they spend half their time making useless wood. Nothing can be done to get such a bush back into shape, as the leg is formed by removing approximately two thirds of the bottom buds before inserting the cutting into the ground.