When to spray apple trees?

Asked May 24, 2016, 3:00 PM EDT

When should I spray my apple trees. We have a Zester & a Honey Crisp. The flowers are gone and we have lots of little apples starting. Last year was the first year we had any apples on the Zester, but nothing yet from the Honey Crisp. Also, is there an organic spraying solution you would recommend?

Hennepin County Minnesota

1 Response

Different pests have different life cycles requiring different pesticide regimens. So there is no simple answer to your question.

The most destructive apple pest is apple maggot:
http://www.extension.umn.edu/garden/yard-garden/fruit/apple-pest-management/maggot/

Good pesticide control of apple maggot requires an almost weekly spraying program beginning July 1 and ending just before harvest. There are no "organic" sprays that I am aware of.

But all is not lost. There is a good non-chemical control for apple maggot: cover your apples with plastic bags. This method is described in the above-referenced document.

Of course, there are other apple pests: apple scab, fireblight, plum curculio and codling moth, to name a few:
http://www.extension.umn.edu/garden/yard-garden/fruit/apple-pest-management/