There is a lot to be said for growing fruit, and for the lazier gardeners amongst us, even more so. You will get crops of many fruits regardless of whether or not you do a good job. But the quality and value of those crops may vary tremendously, and their season of use. The skill is not just growing apples; but in producing sufficiently good enough apples to store and eat over the most months of each year. Each fruit varies with it’s more crucial cultural aspects. Variety, micro-climate, pollination, watering, feeding, pruning, each have greater or less importance for every type of fruit. Often overlooked yet with some your choice of training method can have as much influence as any other aspect of their culture- and will continue to do so through every year of the plants life.
We mostly consider training as merely a choice of aesthetic form; cordon or fan, bush or espalier; a sort of adjunct to pruning. But really it’s that the right training method enables us to prune more surely and effectively. You can easily perceive which growths are in good or bad positions and need removing when you have a clear idea of the shape the main framework is wanted to be. Trying to decide which to leave and which to retain in a free grown bush takes more time than the actual cutting. And we may end up having to do really heavy pruning to sort out the tangle that resulted from our failure to train properly from the start.
In many ways it is much like with a pet; the sooner you start the training the easier and more effective it will be in the end. However unlike with training a pet; with plants sometimes it is possible to hack away previous errors and to start again almost afresh. Redcurrants, whitecurrants figs and grapes are particularly forgiving, their roots are long lived, sprout and can be re-worked many times and in different forms. The same goes for some other fruits especially whilst young and a bush can with cunning be worked over to become an espalier, fan or goblet or vice versa gaining several advantages.
Training enables us to position the fruit so it will ripen better. For example grapevines are often trained parallel and close to the ground to enjoy the hotter conditions immediately above it. In other situations the vines may instead be trained up close under glass roofs with the shape of the framework adapted to the position’s geometry. Likewise espaliers and fans are ‘fitted’ to wall spaces where they benefit from the heat thrown off. Training makes for easier inspection all over, and easier hand pollination if necessary. And allows early spotting of pests and diseases when they are still small enough to be dealt with such as gooseberry sawfly attacks. Ease of accessibility is important- you want to be able to inspect every fruit so you can first thin effectively and then later pick without stretching and grabbing. And for those who use sprays it is also important to be able to cover every surface. Training, especially for say a gooseberry, as a goblet, cordon or espalier, instead of a stool (many shoots from the ground as with raspberries) or a congested bush, reduces mildew problems as the air flow around well spaced trained branches is so much better. Where a bush is failing to ripen it’s crop from over-production, a bit too much shade or poor conditions then re-training to fewer better exposed branches may allow it to better ripen a smaller crop. The things really hard to correct are the occasional poor choice of rootstock such as a strong orchard stock in a confined site and hopelessly wrong positioning say in dense shade. There is not much will help a plant grow in a really unsuitable place and even less to help it crop there. But good training can make the most of a limited opportunity. Training is especially important where you also have confined roots such as in containers or limited space such as under cover. Careful training and support can make relatively small fruit plants in modest containers crop remarkably well and look good too. Left as bushes much of their volume would be unproductive. Open training with well spaced branches allows more air and light to reach fruits and help them colour and sweeten. Even blackcurrants which are usually grown as stools or bushes with the oldest third pruned away each year benefit if afterwards the remaining branches are pulled into an open shape with more space about them.Training thus increases the fruit quality, and of course it involves disposing of unwanted growths so reducing the numbers of buds and then fruits but increasing their individual size compared with untrained trees.
On the down side starting off with a row of trained cordons or espaliers is admittedly more work and expense than filling the same area with suitable bush trees, and the trained forms are more annual work to start with. But as the years pass the regular maintenance of the cordons does not increase by much but the bushes soon require huge efforts, not just to prune but also to keep their crop clean and just to reach to pick it.
Thus cordons, just one branch covered with fruiting spurs per rootstock, are often the best choice, with a supporting framework to keep them in place. Cordons can be vertical but are usually sloped- this makes them longer for the same height. This also helps spread the sap over more buds as sap usually pushes hardest on the topmost almost ignoring the basal ones and resulting in tall leggy growths with few fruiting spurs lower down. With a slope of about 45º all buds receive some pressure and break more evenly with both growth and fruiting spread along the whole length. Likewise we train down the supple canes of raspberries and the blackberry clan, their sap is distributed more evenly and more buds break, at the top of the curve. This gives more side-shoots and crop than if the canes stayed vertical. So cordons are laid at an angle and indeed most other training similarly involves bending branches away from the vertical.
The drawbacks with cordons are their high cost as usually many more are required than with other forms for the same productive capacity. Secondly if the rootstock is vigorous and the soil rich then a cordon may not allow enough ‘room’ for growth and will need continual summer pruning to remove the surplus shoots.
Thus rather than growing just one branch some fruits are grown as pitchfork or trident shapes with two, three or more upright branches however these may only be short because of the top vs basal bud domination. So instead we turn these shoots sideways making horizontal branches in tiers forming the espalier shape. Espaliers can have several tiers but too many and apical dominance comes in again with the top tiers growing and fruiting while the lowermost stagnate. The same danger comes if you train, say a grapevine, with a vertical riser to two or more horizontal fruiting branches much different in height. The higher branch will break sooner, crop earlier and rob the lower one. Better to have two vines, one for the high branch and one for the lower.
With stone fruits their habit of growth makes them unruly grown as espaliers- so they are traditionally grown as fans, or in the case of plums as herring bones. With a fan the branches radiate out from a short trunk and each is laid at an angle helping to spread the sap over many more buds. With a herring bone form the trunk is furnished like an overstocked espalier with multiple tiers of sloping branches.
Of course the more branches potentially the more crop if the roots are strong enough to support them so probably the most common method of training is to the classic goblet shape. The idea here is to have a set of branches curving up around the bowl of an imaginary goblet –each branch cannot be allowed to become too tall to prevent the tops dominating but they make up in numbers with at least five or six of them. Air and light can play on the outside and inside of a goblet’s ‘walls’ as the centre is kept open. I find old bicycle wheel rims, preferably alloy, make excellent frames around which to hold the branches of the soft fruits such as currants and gooseberries. (TIP-If they produce many new shoots from the centre I place a dustbin lid or similar there to make it dark which suppresses them.)
Other more specialized forms have been experimented with; hazel nut trees were once grown to a cartwheel shape where the branches were trained out like the spokes of a wheel then up at the ends to form a giant bowl. Something similar has also been tried for pears and as an effective way to keep cherries down in height. Invented in France the L’Arcure method replaced pruning off strong shoots and trained them down below the horizontal which reduced their tendency to grow. Then the next shoots off these, springing from the highest point in each curved branch, were likewise bent down. The series of arcs were extended in either direction forming an elegant if enormous curvy fan if flat on a wall or frame or a huge billowing cloud shape if free standing. I have adapted it and bend branches down interlacing them thus keeping my cherry trees confined in their cage and peach trees in pots kept columnar so they fit in a smaller space. The cherries respond much better to this training than they ever did to hard pruning!
An important point to remember when starting training is that inevitably it will involve some choice of supports. In practice these are often not well matched, badly skimped and deteriorate faster than the plant. Economy with these is false- make them substantial, solid and long lasting or regret it later. Obviously it is cheapest and little effort to use no supports, however this is false economy. Failure to stake a plant the first year risks bad root development- in this case it is the bottom of the stem not the top we need fix in place, indeed supporting the trunk is weakening it. But we also need something to which we can restrain whippy young branches and later to support heavily laden ones. In either case the old methods tied shoots and branches to canes in turn tied on wires or frames. We now often skimp and tie directly to the wires or framework. This is a serious error, wires rub and cut in too easily, and worse heat up and chill down far too much potentially causing damage which will probably go unnoticed. And do put the frame up first – it is foolish to plant an expensive purchase then hammer posts through it’s roots and breaking shoots off while fitting the crossbars.