Plants have started to react to the lengthening days so that, even if the weather is still decidedly wintry, the pulse of the garden will be quickening. Early spring flowers burst into life, especially during mild spells, and drifts of snowdrops mingled with a smattering of primroses are a joy to behold. This is a gentle reminder that we are running out of time to perform those winter jobs which need to be done while the garden is in tick-over mode.
A classic task to do in February is the final pruning of wisteria. In late summer all the long, whippy, growth should have been shortened, to half a dozen or so leaves, largely in order to prevent it getting damaged in high winds or the sheer weight of it peeling the wisteria off the wall. Now that the leaves are gone it’s much easier to see what’s going on and perform a more considered pruning exercise.
Start by excising all dead, diseased or damaged parts and tie-in shoots which are required to extend coverage or which are necessary to replace older branches due for removal. Once you have done that, and secured your framework of branches, it’s time to shorten all the extension growth and the shoots which flowered last year (these are the ones which you previously cut back to six or so buds in the summer).
It seems brutal but it’s usually recommended to shorten them to just a couple of buds per stem. Reducing the number of flowers that the plant carries will ensure that each one grows to be as large and impressive as possible. Because wisteria arranges its flowers in ‘racemes’ (those long, exotic looking, hanging clusters) the aim is for the wall to be covered in those iconic ‘dripping’ lilac blooms. Reducing the number of buds on the flowering spurs is the best way of achieving this so that, when flowering, the plant is more flower than foliage.
Pruning fruit trees is very similar—actually most pruning in the garden is in order to coax plants into being more productive, in fruit or flower, and to modify their growth in our favour, otherwise we wouldn’t bother doing it!
Stone fruit, that’s plums and their ilk, should be pruned in the summer and only dead wood removed now when it’s most accessible. In most gardens it’s likely to be apples, occasionally pears, that need your attention in the dormant months. I find pruning confusing because no matter how many references you consult there is no ‘blueprint’ that matches any one tree that you come across.
It’s best not to worry too much about the ‘ideal’ but just to remind yourself that any pruning is better than none at all and, if in doubt, then just do very little, waiting until next year to see what results you obtained before attempting any more. If your specimen is truly ancient the chances are it will have reached some kind of equilibrium, growing very little each year, and may or may not produce much in the way of fruit. In that case I’d suggest that the tree itself is your biggest asset and trying to make it productive again could result in losing the lovely mature shape that it’s achieved. Best to enjoy it as it is, treating any fruit as a bonus, and plant a new tree, if you have room, if you really want the fruit.
For trees that are still vigorous I just apply a sort of ‘compromise’ pruning regime which incorporates all the recommendations of the various expert sources I’ve consulted but is not a ‘pure’ method, such as that adopted in commercial orchards. My main aim, as always, is to remove any dead, diseased, weak or damaged shoots and branches. Any plant material that you remove should always be cut back to either a healthy bud or taken cleanly off from where it originates. Never leave ‘spurs’ or stubbly projections which will die back later and which could introduce disease into the tree.
Opening up the centre of the tree is my next aim—creating a ‘goblet-shaped’ specimen is what this is generally known as. This bit is quite simple as you just squeeze yourself into the centre of the tree (you may have to prune off a fair bit just to manage this!) and then look at what you’ve got. Any growth that is cluttering up the centre can be removed, without worrying what kind of shoot / branch / twig it may be, but anything that’s heading out into open air can be left alone at this stage. Once you’ve done this then stand back and consider what is left.
Knowing that soon every shoot will be covered in leaves you can imagine which branches and shoots are so close that they will be shading each other; remove anything that is merely replicating the job of an adjacent portion of tree. Applying the general rule that there should be light and air around between every shoot and branch should help. Any shoot which is thin, feeble and elongated, often referred to as a ‘water shoot’, can be removed entirely.
These non-productive shoots are produced in abundance wherever drastic cutting back, usually of thick branches, has been carried out. Gentle pruning, over a number of years, is the best way to avoid them but whenever a tree is being reshaped it is inevitable that it will react by throwing up water shoots—you can’t make an omelette without breaking a few eggs!
With dead stuff, congested branches and water shoots pruned out it’s time to step back again to assess the overall shape of the tree. I like to keep the tree to a height where all pruning and picking operations can be done without the need to fetch a ladder. This necessitates moving away from the ‘classic’ pruning because, if you read the references, that’s all about identifying whether the tree is a ‘tip bearer’ or whether it bears it’s blossom, and therefore fruit, along the side shoots and branches.
In theory, with tip bearers, you shouldn’t shorten the ends of shoots because you’ll be reducing the yield. I find that unless you want the tree to be thirty feet tall, and therefore mostly out of reach, you have to cut the ends of shoots which point skywards. Always cut them back to an outward facing bud, to encourage the ‘goblet’ shape, and don’t worry about where your tree produces it’s fruit—comparatively few apples are purely tip bearers so it’s unlikely you’ll end up with none at all.
Also, it’s easy to tell at this time of year which buds are going to produce flowers and which ones are destined to be leaves. The leaf buds are little, triangular, scaly things whereas the fruiting buds are fat and rounded. As long as you always leave at least some fat buds, and these may be on the tips of lower branches, or even attached directly to the woody framework, then you will (pollination willing) get apples.
If the tree isn’t yet big enough to be getting out of reach then it’s just a matter of letting it keep up to half a dozen of the strongest stems, which are shooting up and out, as these are the ‘leaders’ which create the branches that are your framework for the future. With these left ‘whole’ it’s just a matter of thinning out anything that is beneath them using the previous rule of letting in light and air plus shortening long growths, which aren’t your ‘leaders’, by up to two thirds. Start by removing a little and then keep stepping back to assess the overall look of the tree before stepping back in to fine tune the shape—you’ll soon get a feel for matching what you’ve got in front of you with the ‘idealised’ specimens you see in books.
That should give you enough to be getting on with not forgetting that seed raising can start in earnest now as long as you’ve got something like a warm, light, windowsill, or greenhouse, to play with. If you didn’t sow sweet peas in November, for a real head-start, then February is the usual month to get them going with plenty of time for growing and hardening off before they can go outside.