Pruning Peach trees to have an open center

Back again regarding peach trees. When we bought/planted our 3 Red havens, the trunks were about 1/2 inch. The existing structure allowed us to remove the central leader and left us with 4 to 5 future scaffolds. I was amazed how the open center unfolded as the trees grew that first summer. We had built 5 ft tall circular fence, 6 ft dia around each tree to keep the pesky deer out.

The second year started with a lot of pruning keeping the center open and they were really taking shape. But during the growing season a few water shoots shot straight up near the center. I had read that we should only prune in the spring so I ignored them figuring I could just prune them off the next spring. Between the dense growth and the restrictive fencing, I didn’t notice how those water shoots dominated. They were major branches and much larger than the starved ones I had anticipated the scaffolds would grow.

The third grow season started with removing the large water shoots. I am beginning to understand how I must keep the center open but encourage new grow where the next years fruit will only grow.

The scaffolds are now covered with vertical shoots 18 inches tall! I expect they will grow much taller if left unchecked. I do not want a repeat of last year where the water shoots take over. I fear they will completely fill the open center. I like all the fruiting wood but…

Do I bend the rule about “spring only pruning” and remove them now to keep my open center?

Cut them back to 10 inches to keep the next year fruit wood? Though vigorous vertical shoots generally don’t have many blooms.

The trees are now 8+ ft tall, so I’m not trying to get height, just planning for new fruiting wood.

It’s not a rule, you can prune whenever you want.

From what I understand, you should do all your major structural pruning when the tree is just coming out of dormancy and there’s no hard freezes in the near forecast. In the spring and summer you can do small maintenance pruning and its better to remove the unwanted branches as early as you can.

The thing to keep in mind is you don’t want to remove too much foliage during spring as that’s when the tree is using up its stored reserves. But you also don’t want it to continue to waste energy on growth that will almost certainly need to be removed in the future.

With peaches its especially important to cycle fruiting wood so you definitely want to remove things that could be shading out future fruiting wood. You will want to have this pruning done by sometime around the summer solstace as thats when flower buds “initiate”, aka decide go from vegetative to floral.

Dimitri,

Thank you. If I have dozens of 18 inch tall shoots off of the main scaffolds, would you recommend heading them off, cut to 6-9 inches? A bit of a compromise, stopping the growth but keeping potential fruit wood? The leaf sets are spaced far a part .as would expected with shoots. Or better to just remove them completely.

I guess this follows with, do you try to regenerate new fruit wood on the main scaffolds close to where they branch off the main trunk? Or keep the first x number of inches of scaffold completely clear of branching, for example the first 36 inches of the scaffold should by without branching.

Personally, I’d head them off now and thin during the dormant time in late Winter.bb

Whatever you read is 100% wrong! Summer pruning is the very safest time to prune and you should only prune sweet cherries and apricots in the summer. When in doubt prune in the summer. You can never go wrong that way.
In general prune in spring to shape structure, prune in summer to control height.
Water sprouts should be removed when they appear.

How do you tell the difference in a water spout and just vigorous vertical growth? If cutting them back gives me fruit wood options as Bradybb mentioned.

Perhaps in areas where bacterial canker is a big problem. Here I prune and have pruned lots of cherry trees in late winter and early spring which is when I usually prune cots as well. But in the upper mid-west where you live cherry canker is a huge issue.

Personally, I have no problem with making large pruning cuts on peach trees in spring or summer- or any other species I manage. Energy lost is mostly energy for the limb removed and the roots that support it.

You can prune peaches before hard freezes fine, it is cold down into the single digits after pruning that can be damaging, or even lethal. The reason it is recommended to prune when peaches are growing is because wounds close quicker and are less susceptible to canker, which is not usually an issue in home orchard sites with very vigorous peach trees- at least in orchards I manage. I’ve been doing a lot of peach pruning in late winter for decades now and the only time I’ve been screwed is when an unexpected plunge brought temps into the single digits 2 days later. The cambium damage that resulted was very upsetting and set back several trees about a year. It killed one of about 15 trees I pruned that day. I’ve never had peach trees suffer from canker.

I’ve been around fruit trees managing them for about 50 years, and every decade has made me less cautious about removing large amounts of wood, as long as danger of extreme winter cold is not in the horizon.

One advantage to dormant pruning is that it is generally believed to be less dwarfing than pruning while trees are in leaf. Of course, once trees have reached their desired size this is no longer necessarily an issue. Then it is a matter of strategizing to sustain moderate vigor, which includes how and when you prune- summer pruning is useful when you need to reduce vigor.

Alex Shigo cautions (or his writing does) that trees are least able to manage the shock of removing branches in fall as they are in the process of hardening off for winter. This may be true, but I love to prune big apple trees that I’m renovating in Sept. here in NY. It seems that it is less likely to cause bark killing cambium damage than winter or spring pruning and it is easier to see how much canopy you are actually leaving.

I think only species like peaches that can be made too tender to cold when pruned in the fall even suffer from pruning at that time. Studies I’ve seen show that fall pruned wounds heal just about as well as other pruning wounds, it’s just the process is slowed down a bit.

Richard Harris covers all this better than anyone, IMO, from a generally tree biology vantage point in his book, Arboriculture, published by Prentiss-Hall. I suggest purchasing a used later addition if you want to purchase it without spending a lot of money. Most important information is included in his earlier editions and cost a fraction of whatever the latest one is. I have his third and it wasn’t worth replacing the 2nd I had before.

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Yes, I found I could not avoid it. But that is what MSU and others say to do. I tend to spray after I prune, that was advice given too. again not advice given for peaches. My biggest problem this year is the soil is too wet. My trees are not happy. Hopefully it will dry soon.

I don’t know Richard Harris’s book. But I read some very intesting articles from a german arborist discussing the common suggestion to prune trees in summer. Backed up by his experience he critizises the fact the suggestion for summer pruning neglects the important fact of reserve material storage. He states summer pruning is an important tool in maintaining trees but it is to be used very cautious, cause it can really hurt the trees ability to store reserves for winter and therefore can harm a tree seriously (even kill it). He clearly states his explanations are not backed up by scientific evidence but in another article he makes clear the common suggestion to summer prune isn’t either. The last word about best pruning time isn’t spoken yet it seems and maybe never will be. There are a lot of factors to be considered.

Here are the links to that articles. They are written in german but the google translator seems to do a reasonable job translating it.

I don’t have an orchard or nearly as many fruit trees as Drew. But, I always did my pruning in late winter. I never gave any thought to post pruning temperatures, the trees were solidly dormant and it gets cold. After reading summer pruning is okay for peaches I decided to give it a try on my peach and nectarine. Not long after both of the those trees got bacterial canker, never had a problem with it before and had some really good and productive trees. In the end, the canker was so crippling that after a couple years of trying to manage it…I just destroyed those trees. No more summer pruning of stone fruit for this guy.
As far as pruning for the open center, are you using branches that are 45 degree angles? Lower degree angles are fine too if the branch can be bent/spread down. The closer to horizontal the scaffold…the more those water sprouts want to dominate.

Not saying you are wrong, cause I don’t know. But one has to be careful to assume a correlation from those one time anecdotal observations. The infection might had happened coincidental after your pruning.

I do my major pruning in very late winter or spring. In summer I only do minor pruning as removing watersprouts and such. I try to avoid removing a lot of leaves in summer. That way I try to get the best from both worlds (winter pruning versus summer pruning).

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Calvin,
Besides reading articles/info sheets from university’s extension services, I listen to advice from experienced forum members particularly @Olpea has he has a peach orchard and has shared his experienced with us consistently.

Like @carot said, the canker and the summer pruning your experience could possibly be a coincidence. However, in the end, it’s your choice to do what you think is best for your peach trees.

I agree, and to hold it above what experts say is usually not a good idea. I have only heard of infections caused by winter pruning on sweet cherries. Also apricots, but other trees I agree it’s the best time. Summer pruning that I do is light to stop vigor and control height.
I do think that late summer pruning is probably not a good idea.
Here in Michigan one of our biggest crops is cherries and Michigan State University says the best time to prune sweet cherries is around August 1st. So that is when i do most of my sweet cherry pruning. OSU and other universities work with them too. I prefer to follow their advice. The financial lives of commercial orchards depend on their advice. They do not make statements that are not well founded in research… One must decide for themselves whose advise they wish to follow.

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I concur. If you make your decision for a well-founded reason thats the best you can do. My goal in posting those articles was to make clear that right now it seems there is no simple and always right answer to the question when is the best time to prune fruit trees (or trees in general). Oversimplifing is dangerous cause there still are surprisingly many questions to examine.

As the arborist in that articles states, to his surprise many experts don’t consider the fact you are hurting the trees ability to store reserves for winter when doing substantial and late summer pruning. The fact itself is known but it seems it is ruled out as a major problem without any scientific proof to be neglectable. From his experience it is not and needs to be considered. If other factors are a pro for summer pruning (eg. disease pressure in winter time) they of course need to be considered too and in some cases it might be best practice to only do summer pruning. But it isn’t a general rule for every situation or even most situations.

Silver disease is the problem with cherries, although peaches can get it too.
Canker is more related to how a tree branches. If you use a bad crotch angle, the bark does not grow right and can grow into tree. Here is where canker reins. So choosing bad branches to keep has it’s consequences. If you make structure correct from the start, you will avoid problems down the road. Timing is important too.

I myself have summer pruned for 7 years now, and it works great for me. I have no plans to stop. I live in a cold zone and my trees are doing great. I do think winter pruning is essential too. For me to manage trees properly I need to prune summer and winter. At least when young. That could always change as my trees are more mature now. My trees this year seem slow to grow, so no summer pruning this year as i want to encourage vigor at this point.It’s too wet for them, environmental stress. Peaches seem to hate it most. I may prune plums and cherries, see when it’s time…

Lot’s of good comments here.

I used to prune “when the knife was sharp”. We still do some, for labor cosidrrations. But it’s best to prune peaches in warmer weather during the growing season.

Here’s a peach tree we pruned a few days ago.

Here’s one we pruned back to nothing a month ago.

We go through and rip out those upright shoots about this time. We don’t head them, we rip them out.

The caveat is that if it’s varieties which tend to produce a lot of blind wood, like Earlystar, we might head some back.

Honestly I can tear off an amazing amount of wood without pruners. Green wood is easy, but if you are agreesive, you can even tear off year old wood. It makes an ugly wound, but there is no downside to being rough with vigorous peach trees during the growing season. To put it bluntly, don’t pussy foot around. You can’t hardly hurt a vigorous peach tree during the growing season.

Vigorous peach trees are more weed than tree.

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Richard Harris is or was a professor emeritus at UC Davis and his book is based on careful research by many scientists, including studying pruning wounds and measuring the speed of healing and comparing the results of pruning at different seasons.

There has been a great deal of research on this subject, actually, partially because it isn’t terribly complicated or expensive to do- to measure how long it takes the wounds to close.

What is complicated is variations of climate and species, but the conjecture of a single man who hasn’t even performed research, let alone include the research of other scientists is not very conclusive to me.

I have witnessed the results of apple trees cut to nothing but huge stubs next to the trunk that could barely recover a fraction of the foliage after an entire season of growth that was lost- and yet ten years later are larger than when they were completely butchered. .

This is the kind of thing people do who inherit trees on a property they only bought for the house.

A weak tree is easy to kill, but a strong one can be very hard to kill- even when you cut it to the ground.

Sometimes we get a snow here in early fall and the tops of trees snap so violently it is like a war zone. Huge wounds are torn into the trees and major parts of their canopies are lost, and yet they almost all survive the abuse.

I hear stories of orchards in hurricanes where the entire canopy is blown off trees in late summer, and the trees survive.

When Drew talks about pruning cherry trees in the summer, he’s talking about what commercial growers do to thousands of trees that their livings depend on. The trees on Mazzard require aggressive cutting- year after year- in summer.

If this was damaging to their survival it would be well known by now.

However, everyone puts very high value on their own anecdotal experience, even though correlations can often be coincidental, even multiple times and even when there is a very logical explanation of why the relationship could exist.

Researchers do exactly the same thing with their research, of course, but they have more data, which presumably makes it more difficult to be tricked by coincidence, but there are always logical leaps involved with interpreting research, and those leaps can land you on mistaken conclusions. This tends to make the public even more trusting of their own anecdotes when they hear repeatedly of research that contradicts previous research.

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I think a lot of what is going on here is well above me. I was just sharing my experience. It could most certainly be coincidence that both my trees got canker after summer pruning. Maybe it is a local environmental risk factor for canker…or…maybe not. Anyway, it was enough for me to come to my own opinion on summer pruning of stone fruits. Pome fruits on the other hand, never had any problems with some summer snipping.

I’ve given a few peach trees canker by summer pruning, but that was when it was middle of July and pruned them hard enough it sunburned scaffolds. When pruning in the hottest, sunniest months, we leave a little more foliage in the middle of the tree to shade the scaffolds. Since I started doing that, I don’t get any sunburn, which turns into canker.

In terms of peach trees, fungal canker grows mostly during the dormant season. Canker can grow at temps lower than the peach wood can grow. In fact, canker grows best when the peach wood isn’t growing. Canker stops growing when temps get hot, which is when the wood really starts callusing.

That’s why it’s generally safest to prune in hot weather during the growing season. Of course pruning late in the growing season has it’s own set of problems, as mentioned by others.

I’m not discounting your experience at all. I’m just mentioning what I’ve read over the years, which matches what I’ve seen.

All that said, there are many times we prune just about any time of the year, at times when we have time. I just prefer to do most pruning during the growing season, if we have the labor. Plus, most of the time we have to prune during the growing season, or we get too much shade. That’s the kind of pruning I mentioned where we rip the new green shoots out by hand.

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Do you find any difference between bacterial canker and fungal canker in regards to what you mentioned above with temperatures and canker growth? Just wondering, my trees had bacterial.