Bloom issues associated with prior season water stress

Has anyone heard about flower bud abortion associated with prior season water stress during the period of bud formation? I continue to have bud abortion on some apricot up to 95% and pluot up to 50%. Sweet cherry have up to 95% abnormal flowers that are infertile but not aborted. I’ve gone through many other theories including lack of chilling. But my chilling has been 1300 Utah hrs the last two yrs with no improvement in the issue compared to 800 hrs.

It’s possible that some of your methods of growing are entering into new territory fruitnut.If so,it may take some time to find out the answers,as I haven’t heard of anyone purposely trying them.I hope someone can help or that the answers are found through your work. Brady

I think dry growers in CA would be discussing that if it were an issue, it would seem an inevitable consequence of their high brix, low water approach as some of them pushed the envelope… Here, during severe drought the apple trees abort their fruit altogether but have flowers and fruit the subsequent season.

When I lived in S. CA I planted some almonds on a very steep hill with sand for soil that never received supplementary water. It amazed me that they survived years with only a couple inches of rain and even normal seasons where 8 rainless months in a row is common. All this without mulch or weed control.

The trees flowered beautifully every spring but it’s hard to know how viable the flowers were because I didn’t watch the results carefully, knowing the squirrels would harvest anything that the trees produced. I know the tree regularly produced a small crop.

Holding back water in the spring is probably not the best way to raise brix from what I’ve read- it is usually done later in the season well after bud formation for apples. I assume peaches and other stone fruit produce flower buds during the entire growing season. That’s made obvious by simply watching the trees grow throughout the season. Fruit forms on every part of the annual wood of stonefruit.

“I assume peaches and other stone fruit produce flower buds during the entire growing season.”


I’ve heard an experienced commercial wholesale grower, first hand, tell a group of peach growers that peaches continue to form fruit buds up to late summer.

But this is different than what I’ve read and experienced. I’ve read (can’t remember where) and seen peaches won’t form fruit buds on new growth after early July (in my climate) and so any summer pruning after July has the potential to reduce fruit the next year.

Peach and nectarine have never failed to set flower buds or to bloom normally in the spring. It’s apricot, pluot, and sweet cherry where I’ve experienced bloom and flower bud abortion. Apricot and pluot set a full compliment of flower buds but the buds abort soon after they begin to swell. Sweet cherry flower fully but are infertile lacking pollen or having deformed female flower parts. There are plenty of other possible causes but I don’t think it’s lack of chilling in my setup.

Thanks everyone for your input!

If it’s still a question of water stress,possibly do a control group test.Give them more and see how they respond later. Brady

Olpea, are you saying that the tips of your annual wood lack flower buds? That makes no sense to me as my peaches continue to form flower and leaf buds throughout the season, It is a pretty easy thing to observe. As long as their is new growth there is the formation of new flower buds. The latest forming ones might be the first to freeze out, however.


I assume when you say tips of annual wood, you mean close to the end but not the very end. The very end of peach shoots never have flower buds, but only leaf buds.

What I see is that any new wood grown after July won’t form flower buds. For instance if I make a stub cut trying to get some renewal wood, the stub will obviously put out new grow, but that growth won’t generally have flower buds on it, if done after July.

My experience has been the same as Olpea’s. You won’t get flower buds on the tips, only leaf buds.

I believe more than the tips form later in the season- that would probably occur around late Aug, wouldn’t it, before peaches set terminal buds.

How far back on a shoot do you expect to see flower buds?

I just checked annual wood on a peach tree closest to my house and flower buds ran up to the end of annual wood on many of the shoots. I can’t understand why peaches would grow differently in the south.

I can imagine the end buds being the most easily killed because the tips of annual wood on trees with an indeterminate growth habit (continuous vigorous growth) tend to be most vulnerable to winter damage and flower buds are more vulnerable than leaf buds. Trees harden up from the bottom up, apparently- at least branches do.

Fruitnut, I’m sorry for hijacking your thread with ad nauseum plant nerd trivia. I just can’t help myself.

I didn’t really word my first post very well. What I’m trying to say is that pruning after July has the potential to reduce crop. I agree shoots can have flower buds right up to the near the tip of existing shoots, so that new growth forms flower buds later than July, so I shouldn’t have made the statement which sparked your objection.

What I should have said was that I’ve noticed that when trees are pruned (after about the first part of July here) and new wood arises (from current seasons leaf buds) because trees are invigorated, the new wood doesn’t have many fruit buds.

I read something along these lines a few years ago and seemed to noticed the same. Last summer was the first time I made a really strong effort to have all my summer pruning of peaches done by early July. In this case any new wood, which is stimulated to grow, puts on fruit buds.

This may depend on how severe the peach trees are summer pruned. Trees here are pretty vigorous, so I have to prune them pretty aggressively to keep them low enough to manage and keep the canopy from getting too dense. This invigorates trees causing current seasons buds to sprout shoots, instead of forming flower buds. In other words, if I prune a peach aggressively, in say late July or Aug., I will get a lot of new growth, but that growth won’t have many fruit buds on it.

I do believe in summer pruning to avoid dead zones from shading we’ve talked about but think it’s best done early summer.

Ah, that explains it. I haven’t even noticed the nature of regrowth shoots- I tend to remove the smallest shoots during winter pruning with my own trees, but here I don’t think we get much regrowth from pruning done after about mid-July, but I will watch for it this year.

I summer prune at least twice- at least for my own trees and my top orchards.