Regular pruning of apple trees is necessary to promote more fruit bearing growths, and therefore more fruit. There are 2 pruning seasons for apples summer and winter.
Summer and winter pruning of apple trees both have different results on the nature of the apple tree's future growth - especially in the first season after pruning.
Training and pruning an apple tree from its first year of planting is desirable and if carried out properly, will have long term advantages over neglected apple trees.
Timing of pruning apple trees is quite important. If the summer pruning is done to early, then developing fruit buds can start into growth when they should be dormant. These buds will not develop fully, and therefore be lost for the following year. Late August is a good time for any summer pruning, and certainly no earlier than the beginning of August.
The summer pruning. Simply prune the current season's growth back 6 or 7 buds from the main stem. This will encourage more fruiting spur growths to form and also transfer more of the tree's energies into building up the current fruit crop. See below for more details...
In the winter, simply prune out any overcrowded fruit spurs, remove any diseased branches and also prune out any 'crossing' branches. Aim also to open up the centre of the tree in stages. Do NOT over prune in winter - as explained below.
With apple trees, remember when 'shaping' your tree, that horizontal branches bear more fruit that vertical branches.
Old, neglected trees are best, treated by pruning over 3 or 4 years. Otherwise there will be excessive growth if you prune too hard. The more you cut, the more it will grow!
Winter Pruning vs. Summer Pruning
There is a basic difference in the results of winter pruning and summer pruning of apple trees. In autumn, the apple tree draws down its energy supply from the smaller branches after leaf fall, and stores it in the main trunk and root system. It is important to appreciate the significance of this, for it has implications for the re-growth of new branches, growths in the spring if winter pruning of apple trees takes place.
Not too Much
If you cut out large portions of the tree in the winter months, you will in effect not be affecting the apple tree's potential for growth the following year - the energy is stored away from your pruning cuts, in the main trunk and larger branches.
The following spring, the apple tree's energy supply - which is geared to what the tree size was before you pruned - surges into spring growing mode. There is enough energy in the trunk and root system to support what was there when it went into dormancy in the autumn. The fact that a large proportion of its growth might have been removed in the winter, means that there is excess energy available, and this will materialise in new vigorous growths in the early spring season - usually at the expense of flower and fruit!
Any pruning in the winter season, should therefore be carried out as late as possible before bud break in order to avert this vigorous flush of unwanted growth. Most of these growths will be tall upright shoot, sprouting out from main branches. These are known as water shoots and have no use for fruiting, though one or two of them can be retained for future training if required. Hard pruning in the winter months will result in much excess growth - taking away much of the energy required for flower and fruit production.
Summer pruning of apple trees normally consists of removing water shoots or water sprouts - much of which can be discontinued if note is taken about excessive winter pruning of apple trees.
As distinct from winter pruning, summer pruning of apple trees results in removing an energy source. The branches are now food or energy producers for the apple tree. Summer pruning should therefore be kept to a minimum, in order to ensure a plentiful supply of food for the tree and its prime purpose - producing fruit!
Summer pruning should start when the new growths are a few inches long, and should be restricted to removing all of the water shoots, and simple thinning of the structure where absolutely necessary. Summer pruning of apple trees should be done in early August and be finished by end of August.
If Apple trees are pruned in July, there is a possibility of the dormant fruit buds breaking into growth. If this happens, the cropping prospects for the following year are greatly reduced. August pruning has the effect of swelling the fruit and leaf buds without causing them to break into growth.
Thinning Cuts. These are simple cuts to thin out the tree as required by taking out a full shoot - right back to another side shoot. They do not cause renewed vigour normally and can be done winter or summer.
Heading back. This is normally just taking out the end (terminal section of a shoot - small branch) and induces new growths at the area of the cut. These new shoots can then be trained into new frameworks as required.
All pruning cuts should be 'finished' as neatly as possible to allow for quick healing. Make your pruning cut as near to the old branch as possible - not leaving any stubs. There is no need to apply a pruning compound or paint to apple trees. They do not prevent the incidence of disease and do not assist in the healing of the cut.
Pruning Apple trees has a twofold effect.
It will retain the apple tree in a manageable size and shape.
If carried out as above, will increase fruit yields.
Remember, that horizontal or near horizontal branches or shoots produce the most fruit.
Branches can be arched over in a pleasing effect, simply by gradually anchoring new branches to the ground, or simply tying bricks or other weights to the ends of new shoot. The latter makes for a good conversation topic!
Pruning apple trees is simple. Just remember and put into effect the advice given above.
By David Hughes