When to thin apples

[ToddG]

I have 6 apple trees on M111 planted spring of 2014. They had a few apples on them last year but it appears they are going to be loaded this year. How do you determine if you are going to thin or not. I have some I planted spring of 2016 on P18 and b118 that are blooming also.
Thanks,

 

[Turkey Creek]

Some will naturally drop off prematurely (June drop). Otherwise I would just monitor and thin as you feel necessary to avoid over stressing the tree or causing limb breakage later in the summer. You can thin apple all through the summer. The only downside is your tree is putting energy into fruit that you might later remove.

 

[aerospacefarmer]

chemical thinning is done at certain apple sizes and you will have to be careful with that type of thinning but its way easier than hand thinning but since you only have 6 trees hand thinning should work just fine for you but getting them sooner rather than later is always better

 

[ToddG]

Do I have to worry about thinning crab apples?
Thanks,

 

[aerospacefarmer]

I wouldn't. They usually are not heavy enough to be a problem. I never have and they do great year after year

 

[ToddG]

I wouldn't. They usually are not heavy enough to be a problem. I never have and they do great year after year

Thank you

 

[chickenlittle]

Todd,

There are a number of reasons people thin.
1. Keep the heavy fruit load from breaking limbs and damaging the trees.
2. Keep young trees focused on getting bigger rather than fruit. Heavy fruiting on a young tree could stunt it.
3. When bears are a problem, removing apples keeps bears out of young trees they might break and destroy.
4. Keep annual production on varieties that tend to go biennial. Set a bumper crop one year and much less the next.
5. Increase fruit size, fewer marketable fruit vs lots of smaller apples

I am mostly concerned with the 1st two. I have trees that were planted 2 years ago. A few fruited last year and I thinned to one or two apples. This year I thinned as I pruned, stripping off some fruit buds from trees that had them. I left a few on certain limbs in hopes the weight pulls the branch down to a better position. I left more on the more dwarfing rootstock I have. I will go through and thin by hand later on if I missed too many. It is already tough to thin by hand as some are 10 to 12ft tall. As they get bigger, I'll just see what happens. Thin in summer with a pole fruit picker if a tree looks like it will break.

 

[Appleman]

Great advice Chickenlittle. The only thing I would like to add is that the sooner you thin after fruit set the more it will encourage a return bloom for the following year and help to encourage larger fruit to develop. Sevin XLR (Carbaryl) is a great chemical thinner for Honeycrisp and Macoun at 90% petal fall. Chemical absorption cuts off carbohydrates to the stamen allowing fruitlets to absend from the tree. I find it essential to use a good thinning agent for Honeycrisp to grow marketable fruit. Most all other varieties can benefit when a heavy fruit set is a concern but may require a stronger thinning agent like NAA be added to the mix for good results.

 

[NE PA QDM]

Sorry if this hijacks but How do you ensure that you aren't killing pollinators when chemically thinning before petal fall?

We have a BAD problem with gypsy moths around us, last year they were chomping away by late April and I have a hard time spraying them in late april and early May without spraying blooming trees. I want to thin with sevin but I don't want to kill pollinators. Any advice?

 

[Appleman]

Sevin is indeed toxic to bees and should be applied late in the afternoon once returned to their hives for the night. We have an apirey in close proximity to the orchard and have witnessed no loss of bees during this period.