Growing apple trees on your allotment
It's not uncommon to see the odd apple tree at the end of an allotment, producing a glut of apples in September, but rarely treated as part of the allotment's productive capacity. Of course you could enjoy fresh apples from July to November, if you planted sufficient different varieties - but that means planting apple trees in the main part of your plot, and your neighbouring plot holders won't appreciate a forest of apple trees shading their lowlier crops.
Fortunately, there is a way to grow apple trees as a proper allotment crop whilst still being a good neighbour. It is time to make friends with the little-known M27 apple rootstock!
As most of you are probably aware, apple trees are usually grafted on to size-controlling rootstocks. The typical apple tree you buy from a garden centre is probably grafted on the popular MM106 rootstock, and produces a nice-looking tree about 12ft-15ft in height and a similar spread. There are quite a few of these at the ends of PAA plots. However, my aim is to show you that you can grow apple trees in the main productive area of your plot - and MM106 is far too big for that purpose. This is where M27 comes in. The M27 rootstock has an extremely dwarfing effect on the scion variety, and produces a mature tree of about 6ft or so - if you stand on your plot with your arms out, that's how big an M27 apple tree will be. This means you can grow M27 apple trees in the main part of your plot without worrying about shading your neighbours.
Gardening books sometimes warn readers away from growing apple trees on M27, because it is allegedly too difficult. That might be true for the casual domestic gardener, because M27 trees are not a "plant and forget" affair in the way that MM106 trees are. However I would argue that M27 trees actually need no more effort than is required for growing, say, brassicas.
The trick is to treat M27 apple trees like a regular allotment crop. Obviously it is a permanent crop rather than an annual crop, so perhaps the best comparison is with asparagus. The big advantage is that these trees are just so compact that you can pack them in at spacings of just over one metre between trees - maybe 1.5m if you are feeling generous. You can grow 10 different apple trees on M27 in the same space as a large asparagus bed - about 2m-3m by a standard allotment width. Alternatively, as a rule of thumb, you should be able to get 4 or 5 M27 trees across a typical allotment row.
Smaller trees means more trees in the same area - and that in turn means you can grow more varieties, allowing you to spread your cropping from the really early varieties in late July right through to November in a good year. Although the trees are smaller than the big trees we currently see at the end of plots, M27 is so productive that you will probably find the total crop produced is greater than the single much bigger tree you might be used to. Depending on the variety, each M27 tree will produce about 4-5kg of apples - the equivalent of about 5-7 supermarket polybags.
What's more, M27 trees mature very quickly - you will be producing reasonable crops just 2 years after planting, and the trees reach full size after 3-4 years.
So what are the drawbacks? Well, nothing that plot holders will find too difficult. The most important thing is to buy some proper tree posts, about 6ft - 7ft high by 2.5". Bang these in about 1-2ft before planting. Then you can plant the trees alongside them. In Pocklington it is best to put the trees on the leeward east side of the post rather than the usually recommended southern side, because the prevailing westerly wind over the allotments will blow them around too much. The posts are essential because M27 trees cannot support themselves - the roots and stem are just too weak.
The other disadvantage is that M27 trees need good mulching and a lot of watering, because the roots are so small. In other words, they do need looking after, in a way that traditional apple trees do not - but I reckon in an allotment environment that won't be a problem, and they are no more demanding than many other allotment crops. You also have to keep the area around the trees completely weed-free and you can't grass around them - M27 trees cannot tolerate any competition.
Perhaps the most difficult part of growing M27 trees, but in some ways also the most interesting, is the early training of the tree into a productive shape. As I have said, M27 trees mature very quickly, so you do have to pay attention to training in those first few critical years. The best (and possibly only) method of training is as a centre-leader, in other words, a bit like a Christmas tree. Buy the trees as 1 year bare-root "maidens", plant them beside the post in the autumn and, although it sounds counter-intuitive, immediately cut the tree down to about 40" high (about 1m) - make a sloping cut just above and away from a bud. The following spring the top bud will grow and become the central leader, and other branches should radiate out below. As these lateral branches grow upwards and outwards, tie them to the horizontal - this is a key part of the training. Ideally you want about 4-5 branches forming the first whorl at around 3ft above ground-level. Note that apart from that initial cut there is no pruning, the emphasis is on training. After the first couple of years, once the tree is mature, there is very little further pruning or training to do.
Another important task: buy some spiral tree guards, otherwise you will find that one dark winter night when the ground is frozen solid and nothing else is edible, the PAA rabbits will eat the bark and take out your entire crop. This is not a risk, it is an absolute certainty, and spiral guards or other protection are essential.
I hope this article encourages more allotment holders to think about growing apples as a proper allotment crop. Unfortunately the method outlined here only works for apples, because extremely dwarfing rootstocks are not available for other fruit trees like plums and pears and cherries. However, in a future article I'll suggest how you can also grow these other fruit trees in the main part of your plot, whilst still keeping the neighbours happy!
For information about apple varieties, see my website www.orangepippin.com.
Richard Borrie, #9.