Ask the Experts Dormant Oil Application for Trees and Shrubs January 16, 2022 Before spring frees us from the season’s cold grasp, it’s best to do dormant oil application for your trees and shrubs. The cold weather can be stressful for them, and throughout the growing season, mites, scale insects, and aphids tend to lay eggs on trees until the winter months when new larvae are born. These newly-hatched pests can damage trees. Fortunately, you can help protect your trees and shrubs with an eco-friendly solution: dormant oil. Applying dormant oil will help control the insects by coating the larvae’s spiracles or the egg’s surfaces. Because the oil is non-toxic to humans and pets, they are considered safe for the environment – and the person applying it. Dormant oil application will give you a good head start on managing pests come spring. Here are some key tips to maximize its application: 1. Observe proper timing Do not apply dormant oil until the tree has gone fully dormant. Application is best done when temperatures are over 40°F and below 70°F. Do not apply dormant oil when the temperatures are too cold as it may expose your tree to damage. 2. Consider other applications Be sure to space out your applications, especially if you also apply a pesticide containing sulfur. A mixture of sulfur pesticide and dormant oil can be toxic to your trees and shrubs. To be on the safe side, allow a 30-day interval after a sulfur pesticide application before you use dormant oil. 3. Achieve full coverage Dormant oils will not completely eradicate all harmful insect life if you do not achieve a thorough spray coverage. Knowledge of the pest, special equipment, and consideration of the tree or shrub’s structure may be needed. 4. Consult with and hire a certified arborist When it comes to dormant oil application, proper spray coverage, timing, and considering other applications may be confusing for some. Getting the expertise of a certified arborist will ensure that your trees and shrubs are in good hands. They specialize in tree care and have the training, experience, and knowledge to provide proper tree care and maintenance. At Southern Botanical, we take a number of preventative measures to ensure that your trees and shrubs grow to their fullest potential. To receive more insights on proper tree and shrub care, visit our blog, The Benchmark, or consult with our Dallas landscaping experts today.