Thinnig - not so simple

Any tree has a certain capacity of fruitit can produce.

We try to manage the size and sugar content by thinning and we have general rules

But there sre other factors that exist and I was wondering if we can use these to tweak the general rules to increase prodiction but still maintain the quality we want.

To keep this shorter.leys talk APPLES.
The general rule is 8inches apart and only one per cluster/spur. Some of thereasoning for the 8 inch separation is so the fruit don’t damage each other what if a branch has 20 spurs that at 8 inch separation would be thinned to 10 fruits.

But what if only 6 fruits took on the branch and what if they are all bunched so close together that using 8 inch separation would leave only 2 fruit on a branch that could suppport 10. But the fruit are on spurs that are on opposite sides of the branch and so no crowding.
Could we leave them all?

Or if a tree had very uneven distribution of fruit so some branches are bare. Could we allow a heavier load on the remaing branches.?

Or heavier on branches that get more light?

All in keeping with the tree’s overall capacity.



Generally when fruit is clustered on certain parts of the branch with lots of empty stretches you leave the existing fruit at closer spacing, but usually not to the point of dividing the inches of the branch by 8 and saving that much fruit.

Leaves closest to the fruit are the ones that support it most- I take that into consideration although I know of no research that provides specific info on this- how close leaves need to be to the fruit to supply how much energy and so forth.

The rule of thumb is about 30 leaves per fruit, but this is a flexible rule as well. Your trees are very open so individual leaves probably provide more energy than trees with more shade. For free standing trees, no matter how well you prune there will be better lit parts of the tree than others. Espaliers are invariably pruned in a way that less leaves serve each individual fruit but each leaf is fully exposed to both direct and wall reflected sun.

A lot of this just can’t be broken down to a simple recipe. You just have to improvise within guidelines. That is part of what keeps it interesting.


I have been struggling with this myself. I have thinned the trees pretty hard and may still have too many apples.

I have some Bud9 trees that are really small trees. It looks like a dozen BIG apples would be all that it could hold up, however I go to Youtube and see videos of the Bud9 tall spindle or whatever it’s called and the trees look solid red.

What about leaving some extra for the immaturely picked fruits by birds/squirrels?

Thinning is dead simple. Some thinning is better than none, and too much is better than too little. Rather than adhering to hard and fast rules, work to develop your own best judgement. There are a number of thinning videos on the Dave Wilson nursery site for general guidance.

I would like to know, why at a local orchard the apples are perfectly shaped, large and the trees are loaded. Thinning does not seem to be an issue. I have a lot of apples on my trees this year; finally but to prevent biennial fruiting I too am thinning. I also lose a few more apples during June drop. I never quite know which apples those will be when I bag them.

My experience is if you get much June drop it means your thinning was too late and or not enough. If I thin early and adequately I have almost zero June drop.

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Same here. I hardly have June drop on apples.

You are right FN. I tightened up my thinning a lot this year and am hoping I see a difference in June drop because of it. Though I suspect I have more room to improve.

Do the U-pick orchards thin?
Does anyone here know?


Commercial growers do almost always thin on good set years and use chemical thinners to do most of their apple thinning but often send out a crew to finish up.

Possible answers to Mrs G’s question about how her local orchard manages such close spacing of fruit.

What thinning is done is probably started shortly after petal fall- trees are given foliar N to boost development and capacity of spur leaves, trees are pruned very open, trees receive dawn to dusk sun, fruit is mediocre quality with lower brix than would be achieved with wider spacing. Irrigated trees can also carry heavier crops of fruit with less threat of biennial issues.

Hi Alan. Can I get a similar N boost from one of the fertilizers such as Miracle grow that list it as a foliage feed or is there a better way to do this on a small scale such as my trees? Thanks, Bill

Like Mrs G I am always impressed at the immense loads the local U-pick place has on their trees.

Personally when I am thinning I go a lot by the size of the fruit already. I am now doing the final passes and I am leaving two fruits on some apple clusters because each of the two are as big as any apple on the tree. A small apple all alone may well get thinned. Each apple tree is different. Later apples you can let hold more for example. My Rambour d’hiver is very late and it gives me a huge load of large apples every year.

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Alan and Scott thanks for your replies. Alan, as you noticed I didn’t mention taste, just mentioned the look of the apples. The commercial orchard apples never taste as good as mine! :heart_eyes: I am just bagging my apples this week. I hope it isn’t too late. My trees did an excellent ‘self-edit’ this year by dropping many of the puny pollinated apples. I just have to brush the clusters with my hand and many of the tiny apples drop off. Now bagging is a different story. That will take me about three days. Scott I too am leaving on a 'couple of fruits if they are both large. It is just nice to have apples!

Has anyone else noticed that when a cluster of apples occurs requiring thinning, that every single one will be nice sized, perfectly shaped and without blemish?
Also that the king always seems to be the one damaged and seldom the queens. Nature does not make thinning easy.

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Auburn, I really don’t know how effective miracle grow is as a foliar feed. I use a product specifically designed for foliar feeding plants with N. It is a special form of urea- the common form is phytotoxic I suspect you could search that out without too much time investment.

I actually used it for the first time this year and am glad, given the heavy crop. It does seem to boost the vigor of the spur leaves. By now there’s probably no point in using it. When the soil is still cool in early spring it is helpful.

[quote=“alan, post:16, topic:1548, full:true”]
I really don’t know how effective miracle grow is as a foliar feed. [/quote]
I have no idea how it might work on an apple tree but I will tell you that I am SURE that it works on a tomato.


Thank You

It absolutely works on a tomato and of course it also works on apple trees, or any other trees for that matter. It’s primary ingredient is urea to the best of my recollection. It also has ammonium phosphate, magnesium (Epsom salts) and a host of other goodies, not all of which are so good.
It is a good product I think in a lot of circumstances, but not all and probably not any for the long term, at least for in situ use.
Really, no chemical fertilizer is really all that great long term, but they have their uses and some distinct advantages.
Trees in general I think would benefit most from organic fertilizers applied at reasonable quantities.
I personally however am not afraid to use the chemical counterparts. I think Alan primarly uses them as foliar sprays which I think is probably the most useful application of them. I’m almost certain of that in trees planted in the ground.
I use them both ways foliar and soil applications. I have problems with hauling organics, otherwise I’d choose that since I could source it for free. Chemicals have edge in that their clean and compact or concentrated.