I’m in Vaughan and I have an apple tree that produces very delicious crunchy fresh fruit. My problem is the worms. What can I do? The organic, blemish free apples in the grocery store seem like a miracle!
Thank you for contacting Toronto Master Gardeners.
The first step to figuring out a solution is to identify which insect is laying eggs in your apple. The following site shows the Apple maggot, Codling moth and Plum curculio. Each has its own way of developing with different life cycles and timing. Understanding which worm you are dealing with will help when choosing a method of control.
There are some things you can do no matter which pest you are dealing with.
Good sanitation practices will help with all apple diseases. Wind falls should be cleaned up regularly with the ground around the tree kept clean of apples and dead leaves including through the winter. This helps if the fallen apples have eggs or maggots in them as it disrupts the life cycle and leads to fewer adults in the area.
Another step that can be taken is putting clear plastic bags around each apple. Leave a small hole in the bag to release condensation and allow some air exchange. If you have a dwarf or small tree this maybe feasible for you. If the tree is large this maybe more difficult to do.
There are different traps available for different insects that you can hang in the tree. This will help with identifying what is attacking your apples and you will know when a population of adults is around your apples. Kaolin clay can also be used to deter adults from laying eggs but it is labor intensive. These should be available at your local nursery.
The last step, which is what most orchards use, is pesticides. Organic farmers use natural pesticides and there are also synthetic pesticides available. If you need to go this root consult with your local nursery to determine what is available and effective in your area. It is important to closely follow the pesticide package directions for maximum effectiveness. Timing and concentration of the pesticide are important for effectiveness. You will need to also follow directions to know what protective wear you need to keep you safe from the pesticide. There are a number of pesticides banned in Ontario. This website gives a list of banned substances.