Pick off leaves to expose fruit to sunlight?

I have 16 mostly semi-dwarf apple, pear, peach and plum trees here in my backyard in NW Tennessee. The orchard is about 5 years old and so far I’ve had very little fruit. This year looks good though for the peaches and plums.
(1) Would it make any sense to pick off leaves that are blocking sunlight to some of the new fruit or does it matter?
(2) This year I’m spraying Monterey Fruit Tree Spray Plus (active ingredients: pyrethrin 0.25% and clarified hydrophobic extract of neem oil 70.00%) on the trees. I’d like to stay organic. So far I’ve sprayed twice. The directions say spray 7-14 days with a maximum of 10 sprays for the season. I thought I’d spray about every 12 days until I reach 10 sprays total. I’d welcome any suggestions.

       Thanks,

           Tom

Tom, could you post a picture of your trees? If the interior of the tree isn’t getting a lot of sunlight, it’s probably advisable to prune out some branches to increase light penetration and airflow, rather than picking off individual leaves.

For question 2, have you noticed any particular issues that would require a spray? My philosophy is that if you’re going to spray at all, it’s better to make sure you have a problem and that your treatment is appropriate to that problem. Otherwise, you could be creating unintentional problems that require further interventions (worst case) or making extra work and cost for yourself (best case). Others may disagree with that take, but that’s my two cents.

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I have found that only early ripening varieties will get fruit ripe before varmints destroy it.

It’s not the fruit so much that needs sun it’s the sugar producing leaves. You want a clear center so all leaves will get sunlight. The sugar in the fruit comes from the leaves. So picking off leaves could make your fruit more tart. Usually people want the sugar.

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I have never done it with stone fruit, but I pick leafs off that covered my grapes when it approaches color up stage.

Yes, it does, at the correct time.

Apples do not need sunlight for growth, but during the ripening period sunlight develop sugars and color.

Take the Japanese way of raising $10+ apples. In the spring flowers get pruned down to one per cluster. Later after the first fruit drop everything that is not perfect gets culled. So far this creates apples that are about 30% larger than the same variety American apples, without shoving a ton o nitrogen that makes them large but watery.

Now the fun starts: Each apple is individually put in two layer bags, an inner translucent bag and an outer black bag. Here the apples grow for 3 months or so completely devoid of light. When the growth phase is done the outer dark bag is removed, at this point the apples are an extremely pale green color. The wax bag has specific hues depending on the apple variety, which filters specific light for optimal spectrum absorption that leads to that perfect color. At this point leaves are pruned, hard. This is fine as the apples are done with their growth phase and what they need is sunlight to develop color and a ton more sugar than they would otherwise. The ground around the tree is covered in reflectors to get the sunlight hitting there to bounce back up. Last but not least apples are rotated by hand every other day or so, to ensure every side is equally exposed to sunlight.

A simplify version is to ensure a very open canopy (18" between scaffolds) and to trim leaves around the apples once they start developing color.

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Since the leaves produce sugar I don’t see how these apple’s would be any good? I guess the apple itself may have chlorophyll? This would not work for plums.I don’t get the removal of the leaves? They pass the sugar almost instantly. Only the closest leaves to the fruit can pass sugar to it. Horticulture 101. So you could remove leaves not by the fruit. That sugar is used for growth of the tree.

https://ipm.missouri.edu/meg/2008/3/Leaf-to-Fruit-Ratios-A-Balancing-Act-for-Sustained-Apple-Production/

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It is not as simple as that and in fact it is incredibly complex. You are right that the primary mechanism is the sucrose transportation cycle and the nearest leaves do the most, but there are other factors at play.

Here’s a neat magic trick: An apple that was harvested at peak time can still get sweeter with no leaves attached to it. Other metabolic processes are still happening where some starches still convert to sugars, and honestly God knows what else. It is beyond my level of comprehension.

But I’ll tell you this; with the amount of science the Japanese has applied to this if they say it works I am inclined to believe them.

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Thanks to all!