Stepover Apple Trees
Training an apple or pear tree as a ‘stepover’ or ‘horizontal cordon’ form is a great way to make productive use of a relatively small space. Stepover trees are extremely compact, making them wonderfully easy to maintain and harvest from. They are often used to provided decorative and productive borders or living wind-breaks for other growing areas in a garden or allotment setting.
The aim of a stepover form is to develop a strong, short main stem (trunk) with two substantial horizontal main branches, and a network of fruiting spurs along the length of those branches.
Spur-bearing varieties of apples are generally more suitable for stepover training than those that are more inclined towards tip-bearing; fruit buds don’t form on first-year growth stems, so if you’re going to prune away the majority of your first-year tips every year, you’ll be removing those potentially-fruiting tip buds on a regular basis.
Of even greater importance is the selection of an appropriate rootstock, which should be dwarfing or semi-dwarfing (i.e. M27 or M9) to avoid the tree growing far too vigorously to be successfully trained1[Edit: March 2023] So, yes, perhaps those two MM106 rootstocks weren’t, in hindsight, the best to use for a stepover form. If I knew then what I know now…. In practice, this either means grafting your own tree (hugely satisfying), or buying a pre-trained stepover on appropriate rootstock from a reputable fruit nursery. Don’t just grab one of those bargain bin trees from a supermarket and hope for the best; chances are you’ll end up with an unruly mess withing a couple of growing seasons.
Our Trio of Stepover Apples
On our main allotment plot we have three stepover apple trees, all of which I grafted in February 2018, using scions from the heritage orchard at work (Ordsall Hall in Salford), onto one M27 and two MM106 rootstocks obtained via our local contact at the Northern Fruit Group.
The three saplings in question were selected from amongst a larger batch of newly-grafted trees. As they grew, these three developed a double-leader – two strong stems growing from just above the graft union – which meant I was able to gently bend those stems and weight them down (using bricks and string), which helped those horizontal branches to fix in place over their first winter.
In year two I planted the trees out on the plot, tying them in to a simple bamboo cane support: a horizontal ‘beam’ of three long canes lashed together, with a similar vertical arrangement in the centre and single canes at either end, and then watched to see how they developed.
I’m very happy to say they all seem to have established well, sending out long primary growth stems in their first year from a number of buds along the horizontal branches, as you can hopefully see below (click the photo for a lager image if the detail is blending into the heap of woodchip in the background).
If I’d followed the traditional pruning advice for trained forms as given in the vast majority of guides, text-books and websites, none of that growth would still be on the tree; I would have pruned it away last August or September. Instead, I deliberately left the side-shoots on the stepovers – and also on the cordons that we have nearby – to grow and develop fully, before pruning them just a week or so ago. It’s part of a trial I’m running to test out some of the theories I’ve read about during my ongoing research project into modern pruning methodologies based on tree morphology, architecture and growth behaviours, rather than historical tradition. Much more about that at a later date.
Making The Pruning Cuts
On this particular stepover there were seven pruning cut decisions to be made, as shown:
The horizontal main stems aren’t included because they haven’t reached the end of the support just yet. Leaving them un-pruned will allow them to continue to grow until they reach the desired extent. In future years they’ll be pruned back to upward-facing buds, limiting the growth to the length of the support.
The cuts I did make were quite simple. Stems #1 to #3 and #5 to #7 – all vertical, or near-vertical shoots – were cut back to 4 or 5 buds out from the basal cluster, to an outward-facing bud. All cuts were made at a downward-sloping angle, to take rainwater away from the chosen bud, which will become the apical bud next season and determine the direction of any re-growth on the stem.
The shortened stems will hopefully provide the basis for a strong fruiting spur network in future years; the length of stem should allow for a cluster of spurs on each, which with judicious selection and thinning in years to come should encourage good repeat cropping on an annual basis.
The one exception was stem #4. That stem was growing out at right angles away from the main, linear shape of the tree, into a space that I use as a path. To reduce the chance of re-growth next season I took that stem off as close to the collar as I could (see centre-pic, below):
Similar decisions and cuts were made on the other two trees. I’ll be monitoring the re-growth of all three trees over the course of this growing season, and will report back at regular intervals.
An added bonus to leaving the pruning of these stepovers to January was that the cut stems are rather excellent scion material, should I want to graft any of these particular varieties:
If I had cut them back in August or September, they would still have been as long, but they wouldn’t have been fully dormant, and I would have had to store the scions in the fridge for a few months, rather using them immediately or just storing them for a week or two.
As I mentioned, I’ll be talking a lot more about the theories behind this particular pruning strategy, and others, in a series of posts later in the year. But if you have any questions in the meantime, please do feel free to leave a comment via the form at the bottom of the page.
- 1[Edit: March 2023] So, yes, perhaps those two MM106 rootstocks weren’t, in hindsight, the best to use for a stepover form. If I knew then what I know now…