|This is how the Victorian kitchen gardeners pruned trees to a fan shape.|
The laterals will produce stems of their own and these can be tied in to about five inches apart as well.
Pruning to espalier.
Pruning is an operation, usually using secateurs or saw, performed upon trees occasionally to give them a desired form or to reduce uneven, superfluous growth that produces a disorganised tree. During this procedure dead, diseased and damaged wood should be removed.
For espalier a one year old tree is headed down to three buds near to the soil but above the graft. Two of the buds will be trained almost horizontally whilst the third bud will grow up vertically. The vertical stem should produce laterals that are about six inches apart and these can be trained horizontally. Other lateral stems can be pruned out together with any stems that are growing outwards from either side.
Heading down or pruning of the main shoot to three or four buds will remove apical dominance and allow the buds left to develop. These buds will form the horizontal branches and a main stem in espaliers and the two main stems for the fan trained trees.
The aim is to establish a tree, by appropriate pruning for the shape, well furnished with branches, leaving no gaps, symmetrical from the bottom to the top and able to produce a reasonable quantity of good fruit.
Pruning is mainly undertaken for the benefit of the many kinds of fruit trees and more especially for the espalier, fan and wall trained fruit trees. It may also be important to annually prune standard trees in order to keep them within the space available to them as well as to promote fruiting wood. However, those trees with space to grow to their full potential in every direction require very little pruning except to cut back any dead, diseased or damaged wood.
Espaliers, fans and cordons, need general pruning twice a year. In summer to cut back obviously surplus branches that have grown in the wrong position during the year and to train in those shoots that promise to be the most valuable for filling gaps and producing fruit. In the winter, pruning is undertaken to tie in and prune the supply of new wood left from the summer pruning and to reconsider old branches where necessary.
The usefulness of growing espaliers, fans and cordons is that it enables several trees of differing varieties and species to be included in a garden without them taking excessive space and shading other valuable plants. Traditionally these trees have their branches arranged regularly to the right and left one above the other so that they are parallel to one another. Aesthetically, a symmetrical tree looks remarkable; however the primary function of the tree, in a kitchen garden, is to produce fruit. This can be achieved with branches five or six inches apart but not necessarily emanating from the trunk symmetrically.
Although I have seen espalier trees pruned with branches twelve inches apart, they can be left separated by five or six inches; forming a regular spread so that the tree covers completely the wall or espalier. As the branches produce a great number of unnecessary shoots and the fruit trees being restricted in the space they have to grow, it is important to take out all the wood that would overcrowd the tree. This enables the main branches to have adequate room, while confining the tree within the space selected for it; together with keeping its shape and correct form.
The growth in the first year after grafting or budding is usually a vertical shoot and the first pruning necessary to espalier, is to head down in spring the shoots produced the first year from budding or grafting. This is usually undertaken in March when the top of the first shoots are taken down to within four or five buds from the bottom.
Reducing apical dominance means that these lower buds can develop and rather than one shoot running up to one stem, the tree will push out several strong shoots from the lower part of the stem during the following summer. This will allow the tree to fill the allotted space of the wall or espalier from the bottom of the tree. Two shoots can be trained straight and regular along the horizontal supports at full length for all summer, whilst one is allowed to form the trunk of the tree and grow undisturbed vertically. During the following winter or early spring, if the main vertical stem has not thrown out suitable lateral shoots and more are needed to form the head more effectively, the main shoot can be again pruned short to four or five buds above the first horizontal stems, which will send out more lateral shoots that can be used to form the next layer of branches on the espalier.
Again these shoots should be allowed to grow to their full length undisturbed during the summer. If the shoots of espalier or wall trees are shortened in the summer apical dominance would be removed and they will push out, and fill the tree with lots of unnecessary and unwanted woody growth from buds along the branches.
However, sometimes this could be useful if there is a void in the tree that needs filling to keep its shape and to make it more symmetrical. Strong shoots can be pinched out early in May or June to four or five buds and these will send out several shoots during the same summer that can be tied in and reviewed in the winter to select the most promising to tie in as permanent branches. Also, as the tree gets older, some branches may need to be pruned short to four or five buds in a similar way to produce shoots to make a better balanced tree.
Pruning short to four or five buds should be mostly avoided in apples, pears, plums and cherries except to fill a void in the tree. All these trees produce their fruit on old wood of from two or three years to many. So, the older branches will be the most fruitful producing the little spur shoots that carry the blossom and fruit.
Having said this, some types of fruit tree need regular general shortening of their supply of shoots to produce new wood. The peach, nectarine and apricot bear their fruit only on young wood in a similar way to blackcurrant bushes. Therefore, each year some branches and stems should be pruned short to force the tree to produce a supply of new shoots for future fruiting. If the main skeleton of the tree is maintained, this can be achieved by cutting back laterals from the main branches.
After the trees have been given a good shape with branches emerging from the trunk and trained at regular intervals they will grow many more stems than are required or can be usefully used as fruit bearers. Some may be too numerous, others ill placed and others growing in an unusual way. All of which, need to be pruned out according to the particular form of the tree.
There must be an effort to divest the tree of branches that are redundant, irregular or damaged by pruning twice a year in summer and winter.
The redundant branches are those, which although good and well placed, are more than are wanted or can be properly trained in.
The irregular branches or shoots are those which are so ill placed they cannot be trained regularly to the wall or espalier. These would include shoots growing outward from the front or back which, though growing healthy, by their position makes them unfit for training.
Very vigorous damaging growth is rank and luxuriant. If left, it will take over the tree and cause the fruit tree to be misshapen and less productive.
The redundant and irregular growth produces a disordered tree and should be thinned by pruning out these shoots close to the collar from where they originate. A supply of more or less well placed shoots should be left to maintain a well balanced tree where every part is well provided with bearing wood trained straight; close to the wall or espalier and at regular intervals of equal distance - or as near as reasonably practical.
Remember, however that some sorts of fruit trees need an annual supply of young wood. Peach, nectarine and apricot bear only on the shoots that are a year old. So some of their wood needs to be cut back quite hard in spring to force the tree to send out new fruiting wood for the following year. Fruit trees, such as apple and pear, bear fruit on old wood and continue bearing for many years requiring only a small supply of young shoots now and again to replace worn out or dead branches.
When pruning, we need to
consider carefully the way in which the tree produces fruit. Peaches,
nectarines and apricots all produce fruit on year old young wood. That
means that the wood that is produced this year will bear the fruit the year
following. This will be the same every year so for these trees it is
necessary to leave a good supply of the best, well placed new shoots each year.
Stems are needed that can be pruned to about 12 to 15 centimetres apart
from the bottom of the tree to the top and to the extremities on either side
and these should be trained at full length all summer. However, these
stems can be shortened less or more, according to how vigorous they are, to
encourage them to send out more lateral shoots the following summer in correct
places for training in and developing the following year’s fruiting buds.
The fruit will be produced all along the sides of these shoots directly from
buds. They rarely form any substantial fruit spurs like apple and pears.
The new shoots produce both fruit buds and a supply of shoots for the
succeeding year’s fruit.
Figs too produce fruit on young, year old wood and need a supply of new shoots each year. It is important to leave these shoots to develop fully and not be shortened because figs bear principally towards the ends of these shoots and if they are shortened it would prune out the fruitful parts. Moreover, these trees usually throw out a sufficient supply of shoots naturally every year for future bearing without the necessity of shortening.
Remember apple, pear, plum and cherry trees generally fruit on spurs growing from old wood of from two to twenty years old. The same spurs continuing to produce fruit for a great number of years. So once you have a good set of branches to give a spreading well balanced head, there is no need for new wood except to replace dead, diseased or damaged wood that has had to be taken out.
Spurs are short robust shoots of from about one centimetre to three centimetres long arising naturally on the branches of two or three years old. As the branches increase in length the number of fruit buds increase. So, in the general course of pruning, in all these trees, their branches must not be shortened. They should be trained in at full length because if they were shortened it would remove the wood where the fruit buds first appear and instead would produce a number of strong unnecessary wood non fruiting shoots from all the remaining buds.
All the shoots or branches of these trees should be trained and tied in at their full length and as they grow need to be left entire because then they will readily form spurs from most of the buds along their length.
In the general course of pruning all trees trained as espalier or fan, when cutting back superfluous and badly placed wood, it is important to cut right back to the collar close to the branches or stem they originate from both in summer and winter pruning. Stumps or spurs should not be left in the hopes that they will miraculously convert themselves into fruiting spurs. All that will happen is the tree will push out lots of wood from every bud on the stump and the tree will become crowded with a multitude of unnecessary and irregular shoots. A lot of the energy of the tree will be diverted into growing these shoots to no purpose and a great deal of time will be needed to prune them out.
All shoots and branches that you need to prune out should be taken off quite close to the place they originate from. In the summer small woody stems can be rubbed out with the thumb; however when the stem become stronger and during winter pruning these irregular shoots will need to be taken out with a secateurs cutting as close as possible to the collar.
In the general course of pruning in summer, the trained stems and branches should never be shortened unless to fill a gap because by shortening them in summer all the shoots so treated would soon grow vigorously from every bud and produce a thicket of useless stems. So for all sorts of fruit trees, be they stems and branches that will need to be shortened in the winter or not, should during summer pruning just be tied in at their full length. There are two seasons for pruning for any tree grown as a wall, espalier of fan. These are in summer and winter.
Summer pruning is very important because during spring and summer wall and espalier trees will have grown a great number of young shoots that need to be thinned out to maintain the symmetrical shape of the tree and to encourage the production of fruiting spurs. The sooner this is done the better. This work can be started in May or early June. All growth that is judged to be unnecessary or overcrowding the tree can be removed easily before they have grown large and formed a disorderly tangle. However, the summer pruning should not be undertaken until the shoots are sufficiently formed so that useful shoots can be identified and tender enough to be pruned out easily if they are not.
The summer pruning should be started before the growth of new shoots overwhelms the tree and makes it difficult to identify wood that needs to be retained and that that needs to be pruned out. It is important to do this in May or early June when the new shoots are sufficiently formed to enable a proper choice to be made and the shoots are tender enough as to need no other instrument than the thumb to displace the unnecessary growth.
This summer pruning needs to be undertaken before the trees have shoots so far advanced as to cause much confusion which would cost a great deal of time to penetrate through and determine what is proper to prune out and what to leave.
However, if it seems important to keep the vigorous growth because it fills a space in the tree well, then it can be cut back to four or five buds and produce a similar number of shoots which will probably be more moderate in growth.
If the whole tree is apt to produce vigorous growth then the best can be trained in. Moving the stems to a more horizontal position may slow the growth a little. Also leaving the stems full length without taking anything off the ends will enable the tree to be structured while allowing it to grow vigorously at the extremities. Doing this will more readily slow the growth of the tree and make it produce new wood a little more moderately.
Good attention should be paid to the bottom of the tree because new shoots are often found there and these can be used to be trained in or as replacements for tired old wood. So, if this wood is growing strongly and they are fairly well placed, then they can be left in place until the winter when they can be properly assessed and trained in if required.
All weakly or spindly shoots should be taken out unless they seem useful to fill a void or likely to be of service later.
After summer pruning and clearing the tree of all useless shoots, the remaining shoots should be directly trained in straight and close to the wall or espalier and all of them at full length during the summer. None of them should be shortened at this time except where there is a void where pinching to three or four buds might be appropriate.
Having trained in the stems, it will be necessary to assess them again occasionally in order to prune out or tie in such branches that have taken a wrong direction. Any branches produced later in the summer that are growing irregularly will need to be trained or cut out.
The main branches that have been left at full length will have grown longer and these will have to be tied in. In order to maintain the shape and form of the tree, all new growth needs to be carefully maintained and kept close to the wall or espalier and if this is done carefully the trees will appear beautiful and the fruit will be abundant. Fruit will have the advantage of receiving sunlight, air and water throughout the tree and produce better for it.
In the winter pruning both the main branches and the young wood that has been layered in during the preceding summer with need to be undertaken. The correct time for this pruning is any between leaf fall in November to the following March.
When undertaking winter pruning the branches should be taken off the supports particularly when pruning peaches, nectarines, apricots and vines. However, it is equally important to do this with other fruiting trees so that a proper assessment can be made.
First you need to assess all the main branches and see if any are worn out or not furnished with spurs or fruiting laterals. The worn out branches need to be taken right back to the main branches or trunk of the tree. However if there are strong laterals that they support nearer to the trunk or main stem, the branch can be pruned back to these branches so that they can be trained in to replaced the lost wood. If any of the main branches are becoming too long for the space they have been planted in either at the sides or at the top then they will have to be shortened accordingly. This can be done by shortening them to a lower shoot or branch situated somewhere along the branch to replace it. Care being taken to make sure that every branch terminates in a young shoot of some sort for a leader and not just stumped off at the ends.
When the main branches have been dealt with, the wood produced the previous summer which was trained in during the summer pruning needs to be checked. As before all the wood that is outward growing and that was missed in the summer pruning should be taken out now. Also the weakly growing shoots and those of very luxuriant growth unless it is felt necessary to keep them to fill the tree a little more symmetrically. Some of the remaining strongly growing shoots will be needed for the next summers baring as in the case of peaches, nectarines and apricots and these should be trained in regularly along the branches.
Very few of these shoots left after the summer pruning will be necessary to keep in apples, pears, plums and cherries except to replace dead, diseased or damaged branches.
As peach, nectarine, apricot, grapes and figs always bear principally on the new growth of last summer this must be left in every part of the tree from the bottom to top at regular distances apart. All these fruiting stems should be shortened a little according to their strength to encourage them to produce a supply of shoots in spring and summer for net year's bearing. The strongest growing shoots should be left the longest.
This pruning procedure should not be done on figs because they bear fruit on the extremities of shoots. These shoots must not be shortened in any way.