In January last year I posted an article about winter pruning stepover apple trees, explaining why I’d deliberately left them un-pruned until winter, rather than cut the vegetative growth back in summer, as is usually recommended.
I’ve done exactly the same this year, and although I couldn’t prune in January as we were in the midst of a cold-snap, the pruning has now been carried out. Here’s what I did this year, and why.
We have three stepover trees on our main allotment plot, each one grafted onto M27 rootstock in early 2018, grown on for a year in open ground at work (Ordsall Hall), and then transferred to our allotment in early 2019.
All three varieties – ‘Howgate Wonder‘, ‘Keswick Codlin‘ and ‘Blenheim Orange‘ – are ‘dual purpose’ varieties, suitable as cookers or dessert apples if left to fully ripen. In a good year all three also produce reasonably large fruit. This might make them odd choices for a size-restricted tree form, but because I also carry out rigorous fruitlet thinning in May or June, in a good year the trees should be perfectly capable of producing 6-8 well-spaced, good-sized fruits per horizontal branch; 12-16 per tree. That’s not a massive crop, but it’s a decent return from a relatively small commitment to growing space.
Last year’s post includes photos of the trees after one year’s growth in-situ, and here they were earlier this year, mid-chill:
As you can hopefully make out (a dusting of snow is rather handy for providing a reasonable background for photos) all three trees put on quite a lot of new growth last year. You can see the strong vertical shoots that have sprung up from the horizontal ‘leader’ branches. The strongest growth was on the ‘Blenheim Orange’ – generally considered to be a vigorous cultivar whatever rootstock it’s grown on – but the other two weren’t far behind.
If I’d followed the standard advice given in most fruit manuals and pruned these trees in the summer, there’s a good chance – given the vigour of the trees and the very mild autumn we had last year – that this would have resulted in fresh re-growth late in the season. That soft new growth would then have been more vulnerable to damage from this year’s hard(ish) frosts, whereas these more mature and robust stems have coped just fine. That’s one good reason not to carry out summer pruning, which is a topic which I’ll be returning to in much more detail at a later date.
This Year’s Pruning
Stepover Apple ‘Howgate Wonder’
This tree didn’t set blossom last year and I removed aby fruitlets that set in 2019, so we’ve not had a harvest from it yet. I’m hopeful that we’ll get apples this year though.
Here’s the tree before I started pruning, showing good extension growth along the horizontal leader branches:
Here’s the end section of the right-hand horizontal leader:
To prune this tree, I simply cut back all extension growth to two or three buds from the basal cluster, cutting to a bud that was pointing outwards to avoid awkward re-growth. With any luck this will encourage the development of fruit buds, which only grow on wood that’s two or more years old, and then fruiting spurs – clusters of fruit buds on short, sturdy stems – in years to come.
I left the tips of the leaders un-pruned, as they haven’t reached the desired extent just yet (the original cane supports were removed before this pic was taken; I’m planning to replace them with something sturdier and re-tie the leaders before too long).
Here’s the central portion of the tree, post-pruning:
I’m expecting re-growth from several points along the leaders, but I’m hoping it won’t be quite as vigorous as last year. Potential fruit buds have formed at several points along the branches and will hopefully develop into fruiting spurs:
I say ‘potential’ fruit buds because, although they’re the right size and shape to produce blossom clusters, if the conditions – weather, temperature, water, nutrient supply, etc. – aren’t right then the buds could remain dormant for another year, or even revert to vegetative growth instead. But if they do flower, and fruit is set, then the energy and nutrient demands of the growing fruit might help to check the amount of new stem growth. Maybe. We’ll see.
Stepover Apple ‘Keswick Codlin’
This tree rather casts doubt on my previous point about fruit development checking re-growth; it produced six or seven good-sized (and delicious!) apples last year and yet it still managed to put on an impressive re-growth spurt:
Viewed from the trunk out towards the end of one of the horizontal leaders, you can see that the main branch hasn’t grown straight and true, but with a new support in place and a bit of gentle persuasion that should be correctable:
Judging by this cluster of potential fruit buds, I can look forward to another crop from this tree this year, and the development of a strong fruiting spur network in years to come. That bud on the right is a tricky one, very close to the stem, but I’ll see if and how it develops and can always thin it out if necessary:
I applied the same general pruning regime as before; cut back to two or three buds. One leader was trimmed, the other was left to extend a little more. Here’s the tree once the pruning had been completed:
Stepover Apple ‘Blenheim Orange’
This variety of apple has a reputation for being quite vigorous and our stepover is certainly doing its best not to let the side down. No cardboard background in this shot as I didn’t have a sheet large enough to fit in all the re-growth:
Out of shot (and difficult to get into a decent photo) the growing tips of the horizontal leaders had also extended a good metre or so beyond the end of the supports and were curving upwards. To give you an idea of quite how much re-growth this represents, here’s the same tree in April 2020, showing last year’s pruning and with its new crop of leaves just beginning to sprout:
Here’s the re-growth point along the leader, where the tip was pruned last year. This is about as good a re-growth pattern as you could hope for: the scar from the previous wound – the ring of paler tissue in the centre – has healed very nicely, and the extension growth hasn’t come away at too awkward an angle. In time, as that branch thickens further, the scar will hopefully merge completely into the developing branch:
This is another tree that’s yet to fruit, but again, it’s carrying a decent selection of potential fruit buds. Here’s one of last year’s bourse shoots, with (clockwise from left) the scar from a blossom cluster (that unfortunately didn’t set), a potential fruit bud, and down at the bottom either a possible vegetative growth bud, or the scar from a brindille stem that was trimmed last year. In any case, it’s starting to show signs of healthy fruiting spur development, which is just what we’re looking for:
Here’s the tree after pruning; again I took it back to two or three buds from the basal cluster of each stem. I also cut back the leaders to the length of the (soon to be re-installed) support structure, as I really don’t want them to continue to grow upwards.
Hopefully this year’s re-growth won’t be quite as enthusiastic. But knowing ‘Blenheim Orange’ it will be reaching for the sky again by the end of the year.
I hope you’ve found this long-read piece interesting. If you have any questions about the pruning method, or the timing of the pruning, please feel free to drop them into the comments. Although, as I mentioned earlier, I will be exploring the wider topic of winter vs summer pruning for a range of tree forms in much more detail in a series of future posts. If that’s a topic that interests you, please do sign up for my email list for a weekly digest of posts from the site, and you’ll be notified when the series starts.