Dormant Oil Sprays Can Be Applied in Late Fall When Leaves are Off Trees

I have been asked many times what is a dormant oil spray and about its use in the maintaining the trees and shrubs in your landscape.
　
Dormant oil sprays are specific horticultural oils which when applied with the addition of copper fungicides or lime sulfurs suffocate the insects and destroy the disease carrying fungus which over winter on the tree.

With fruit trees, the dormant oil and fungicide combinations will control mites, scale, aphid eggs, leaf curl and shot hole fungus to name a few insect and disease pests which will attack and prevent successful fruit production.

 For those of you who wish to use an organic oil spray there are some composed only of cottonseed oil and there are some recipes as how to make your own spray. I would recommend searching the internet with the phrase "organic dormant oil" and you should successfully locate commercially prepared dormant oil sprays or do-it-yourself recipes.

I did locate one site, Chari's Bugs Online which had recommendations for a commercial organic oil spray as well as a home made recipe.
　
Regardless, oil sprays can be applied in the late fall when leaves are off the trees and temperatures are not freezing. When applied in the early spring, the dormant oil spray is applied before the leaves of the trees and flower buds have emerged.