As stated before, most of the fruit quality benefit from thinning fruit occurs during the last 3 weeks or so before harvest. Earlier thinning of apples can help cure biennial bearing but for fruit that bears reliably the main benefit of early thinning is getting larger fruit, most of the sugar enters the fruit shortly before harvest. Also, branches obviously are threatened as an overburden of fruit gets larger, with danger increasing the closer you are to harvest.
Here’s text and video that should help guide people. Maybe Olpea has a video he made himself he could add to this topic. Beginners tend to be too careful and the job can be very tedious if not done rapidly.
and read this- next year’s peaches will tend to be on less vigorous shoots and the most vigorous growth that will be pruned next year can be much more profitably (to the fruit) pruned now, or a month ago. Shaded leaves can’t gather the energy to make sugar for your fruit. Prune to bring sun to the leaves that serve the fruit while you thin it. Excessively shaded leaves can permanently lose their ability to photosynthesize after a few weeks of deep shade.
Here’s a basic rundown but this applies to other fruit as well.
what is the breakdown on leaves delivering sugar to peach fruit as far as relative distance. How close do leaves have to be to make a significant contribution.
ChatGPT said:
The contribution of leaves to fruit growth in peaches is highly localized. The general consensus from decades of carbohydrate partitioning studies—especially using radiolabeled carbon isotopes—is that most of the sugars (photosynthates) that go into a developing peach come from nearby leaves, typically:
Primary Contributors:
Leaves on the same shoot as the fruit, especially those within 1–3 nodes above or below the fruit.
These are considered source leaves, and they supply the majority (often over 60–70%) of the sugars needed for the fruit’s development.
Secondary Contributors:
Leaves on nearby shoots, particularly those on the same scaffold branch, can contribute modestly—especially if nearby source leaves are removed.
Contribution drops sharply with distance. Leaves more than ~20 cm (8 inches) away provide little to no sugar to the fruit under normal conditions.
The rule of thumb is that it takes about 30 leaves to nourish a single good sized peach or apple or pear- probably about half that for plums if they are pretty big ones.
This year I got tons of fruit to set. Especially the pluots. So easy to grow here. Well not always. Some are, some are not. Flavor Queen has not ever set more than 2-3 fruits a year. This year it grew over 40. Wish I knew why? Hope it keeps setting every year. The flavor is tropical. One of my favorites. I have heard they are too sweet in California. Not here sweet but not enough to kill the subtle flavor. Ripen early too. They should be ready in a couple weeks.
I thin a little at a time until harvest. Often missing a lot if I rush
I’ve got a few apple trees that are loaded with fruit this year. No June drop to speak of.
Last year my peach trees were loaded and even with thinning them about this time of year there was plenty of peaches. So many in fact I had taken them to the food back and shelters. They were happy to actually get some fresh locally grown fruit. This year I have about 6 peaches on my 4 peach trees. What a difference between last year and this year with peach production.
In my opinion Mike, is that your trees overproduced last year. It strained the tree the branches damaged from all the weight. Thin more next year. Often low production is a symptom of overbearing previous years.
Vigorous peach trees can overcrop year after year even without thinning, but if branches were bent below horizontal by the weight of the excessive crop or if trees are not very vigorous anyway, I would agree. In my experience, new shoots always have flower buds on healthy peach trees. If the tree is so burdened by crop or environmental stress it won’t grow those shoots, but it isn’t like apples that will bear fruit on spurs that don’t always produce flowers so can be bienally fruiting.
Yes, I agree with you. Probably the overproduction of fruit last year. I even thinned the trees out twice before the fruit got ripe. Just every branch had fruit on them, for once.
This year the peaches blossomed some but no fruit.
This year there are a lot of branches that appear dead. No leaves and brittle. The peach trees are about 12 years old. From what I have read the life expectancy of peach trees is not very long, maybe 10 years or so. I just figure these are at the end of their usefulness of fruit production. I will see what the trees look like next year. It may be time to take them out and replace them with new peach trees.
I do have one newer peach tree, planted in 2017. It had some very nice peaches on it last year, first time it had an actual nice crop. It has zero peaches this year.
I should update my zone to 6 on my info. However, it still has the same effect regardless of zone 5 or 6 here. I knew my zone would be a hit or miss with getting any peaches at all.
I figured a few home grown peaches are better than none. That was the reason I planted 4 peach trees - to get some, I figured they would not produce a lot of peaches. When my trees have a good year I get a LOT of great peaches. I have had good peach production probably about every 4 years time or so. I capitalize making peach preserves and freezing peaches when I get one of those high production years.
Some areas do get a lot of peaches regardless- lucky people.
How cold did it get there this winter? Our winters have become milder, but when we get sudden dips into negative numbers F. all bets are off- trees just don’t harden off as much as they used to because of warm falls and relatively mild winters. It is common in my orchard for the male parts of flowers to survive when the ovules are killed, so you get beautiful bloom but no fruit. Is there a relationship between dead or injured trees and relative hardiness of varieties? There is also the question of the condition of the trees going into dormancy and of the soil. If the trees are stressed with too much or too little water in late summer and going into dormancy, they may not do a very good job of hardening off.
Anecdotes muddy up diagnosis when not including all of the evidence. Fruit trees, like all plants, are very complicated. I seriously doubt your problem was exclusively overbearing, especially given that you at least attempted to properly thin your trees. Peach trees aren’t like apples and mostly decide on whether to set flowers in spring, they keep making flower buds through much of summer.
I agree reasons can be complex. I don’t always know why certain things happen. This year my blueberries were almost all dead. One out of seven plants was unharmed. A couple were completely killed. The others damaged enough to stop production. It’s going to take a few years to get these plants healthy again. Yet my fruit trees are perfect. No issues at all. The one heathy blueberry is legacy. I’m going to get more of those. The fruit quality is excellent.
Never had an issue the past 12 seasons with my blueberries. I have no clue what happened?
Also my wyeberries usually lose half of their canes to cold. Not this year. All survived and a massive amount of berries is ripening. A few hundred at least. These are beginning to ripen now. I had black raspberries. Red, pink, yellow and purple raspberries, wyeberries and gooseberries mixed in yogurt with almond slices for breakfast. Delicious!
It did not really that super cold this winter, from what I can remember. All it takes, like you mentioned , is a week or so or below zero temps to throw peaches or any other fruit off their game. There are so many variables to consider to try and figure out why the fruit trees are producing fruit. Too much fruit the prior year, weather temps wide swings, not enough rain before winter, too much rain before winter, etc… Like you mentioned plants are complicated.
I knew it would be a spin of the wheel of “fruit- no fruit” years.
One orchard one site, but it’s your site. I manage over 80 orchards in different soils and a slight range in zones, but I cannot expect people to put a high value on my own anecdotal evaluations- we are all fallible in that department and amplify the importance of our own experiences.