Horticultural Oil Application to Fruit Trees
Posted December 05, 2017
Winter time is the time to spray fruit trees and small fruits species with horticultural oil (also called dormant oil) to decrease insect populations and minimize seasonal insect build-up.
Horticultural oil is probably one of the most important sprays that can be applied to fruit trees. It is classified as an insecticide and miticide. It is used to smoother soft bodied insects such as aphids, scales, mites, thrips and their eggs. It will also suppress peach twig borer.
Horticultural oil can be used alone as a dormant oil, or it may be added to fungicides or bactericides as a spray adjuvant. Combining Horticultural oil with a copper fungicide will greatly reduce diseases such as coryneum blight or peach leaf curl.
Horticultural oil spray should be applied after the majority of the leaves have dropped and before the buds swell or before new growth starts in the spring. It's best to spray when temperatures are above freezing for at least 24 hours after application.
It is important to make thorough coverage when you spray, taking care to spray bark crevices and cracks where insects may be overwintering.
We recommend three sprays during the dormant season. First should be done after leaf drop, second 4-6 weeks after and again 4-6 weeks for the third spraying. Holidays are an easy way to help you remember spraying times. Thanksgiving, Christmas and Valentines, give or take a week or two.
Horticultural Oil is regularly used on apple, peach, plum, pear, quince, apricot, nectarine, grape, blueberry, blackberry, gooseberry and others.