How to summer prune: Belgian Pear espalier...

21 February, 2015

Now is the time to summer prune, being late summer, unless you are more organised than me and have already done your summer pruning.

But what about you out there saying "Summer prune??? I thought you always prune trees in winter?!"

Well, it depends.

If you want to encourage your tree to grow lots of new growth - winter prune.

If you want to encourage your tree to stay small but produce lots of fruit - summer prune.

I know which outcome I'm after.

Generally deciduous trees (including fruiting trees like pears, apple, peaches, plums, nectarines, cherries etc) like to keep their root system and leaf growth equal. In summer an untrained tree will use the sunlight to make energy and grow as big as it possibly can, and produce as many fruit as possible. Then when the tree goes dormant over winter the tree sucks as much energy as it can into its root system, ready to grow nice and big and produce lots of fruit come spring. If you then cut the tree back in winter, come spring the top growth is way out of whack with the roots, and the tree then wants to reestablish the balance by growing lots of top growth. It will still fruit, but all this growth can be counter productive if you are aiming to keep the tree small enough to manage. After all, what is the point of having a tree too big to pick the fruit?

Summer pruning encourages two things: 1. the tree then wants to keep the root:leaf ratio equal, so curtails root growth, and 2. the tree feels threatened. Something is eating the tree. The tree thinks ('cos we all know trees have thought processes) "better put all my energy into fruiting lots next season to ensure survival of my delicious pear genes, just in case these tree eating things stay around". Or something like that. So the tree puts energy into not growing too tall and making lots of fruit. That's the tree I want in my yard.

Of course, summer pruning may not always be appropriate. Young trees you are shaping, or any tree retraining, may be better to winter prune, so you can encourage the growth you want in the next season. But if you have a fruit bearing tree, summer pruning is the biz!

So, anyhoo, back to the pruning.

The Belgian Pear espalier has been looking a little messy. You can barely see any shape, no beautiful diamond shaped criss-cross of plants evident here.


Time to get the secateurs out.

In this instance, not only am I summer pruning to encourage fruiting, but also to reestablish the shape of the espalier. So any branches not growing in a direction conducive to the look of the espalier are first to go. Then any crossing branches, or branches growing too close are either removed entirely (chopped back to the main branch) or cut back to a fruiting bud (more on that later).

The main branch growing tips are then tied to the framework to keep the whole thing looking tidy.


Ah, that's better. At least you can see more of the main shape. Some of the trees are more vigorous than others, so have reached the top of the espalier. After they reach the top I'm letting them grow wild, to see what I end up with. These are dwarf pears (double grafted onto quince rootstock) so are supposed to only grow 2-3m tall, so we shall see what we end up with.

Now, what was that about fruiting buds. Ah yes.

Fruiting buds = flowers = fruit. So the more the better.

Fruit buds are fat, where leaf buds are skinny.

If I see a fruit bud like this, I leave it (so long as the branch isn't otherwise removed for reasons above).


However, sometimes you need to cut back branches. In doing this you can try and encourage the plant to make a leaf bud into a fruiting bud. (I don't completely understand how this works, but apparently its all in the tree hormones.)

Look for a little bud next to a leaf, growing in the direction you want the branch to grow in, and cut above that bud.


Generally you are mean to cut just above the bud (like 2-3mm). But I was given a tip last year that was to cut quite a lot about the bud. This encourages die back in the branch, which in this instance is more likely to produce the plant hormonal mix that develops a fruiting bud. So I'm giving this a go.

I'll also be posting on how I summer prune my peach trees, cherry trees and step-over apples.

So what are you waiting for. Get out there and summer prune!

16 comments:

  1. I summer prune my espaliered trees. Not to keep them from growing, but because they are easier to shape that way. It does make them grow slowly though and I want to them to fill out their spot.

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    1. True, that is a downside. But I'm sure they will be beautifully shaped trees.

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  2. Very useful info! I'm off to summer prune! Sometimes, when I've cut too far above a bud, the bit left dies back to the bud as expected, but then doesn't know when to stop and keeps dying back below the bud. Have you ever found that?

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    1. I've never yet had that happen. But I can't explain why.

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  3. In our area, it's actually best to prune some trees (sweet cherries & plums, are two that I know of) in late spring or summer because they are then less susceptible to certain diseases. Good thing too as I only have a cherry & plum so far and the thought of going out there and pruning in sub zero temps isn't that appealing ;)

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    1. Interesting. Yet more evidence that gardening lore is only useful in your climate/conditions. It doesn't always extrapolate to other areas. Yes, I can see that winter pruning in the middle of snow season wouldn't appeal :)

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  4. Thanks for the timely inspiration and guidance.
    I will now be pruning my row of pears in the next few days
    They are on Pyrus calleryana D6 rootstock, which can be large and vigorous, I think.
    I totally agree about the great importance of keeping the trees small and manageable.
    Maybe this won't be too successful with non dwarfing rootstock, unfortunately.

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    1. No problem. I have no idea about that rootstock. I know a little about apple rootstocks, but that's about it. I have a vague recollection that most pear rootstocks aren't very dwarfing i.e. they turn a 30m natural pear tree into a 10m tree, which is pretty dwarfing by percentage, but still to big for the average backyard. That's why the very dwarfing (i.e. 2-3m trees) are double grafted onto quince, which is more dwarfing.
      Either way, summer pruning will still likely help to inhibit the tenancy of the tree to grow as big as it can and help it to direct more energy into fruit. Good luck.

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  5. OK thanks again Bek.
    I did some pruning of my pears and apples today.
    A possum had helped me do some of the apple tree pruning already.
    How considerate of him :)

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  6. Hi, Bed
    Interesting post. Thanks. have you seen this video clip of Margaret Siri snapping pear twigs to encourage fruiting? I think it's a fascinating technique, but I haven't tried it yet.
    http://www.abc.net.au/local/videos/2011/11/22/3373321.htm

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    1. No, I haven't seen it, but will be checking it out now for sure! Cheers!

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  7. Menat to say, Bec, not Bed. Sorry!

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  8. Did you get pears this year?

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    1. Yes, I did! There was the one in the above pictures (low down on the second tree from the left) and about 16 on the free standing Durondeau pear in another area of the garden. I am hoping for more next year, as they were delicious!

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