Mother Nature has teased us this past few days. We’ve had temperatures in the 70’s with brilliant sunshine. Working in the orchard felt great, no layers of coats, gloves or insulated work boots. Great progress was made in finishing pruning, cleaning the aisle ways and picking up any pieces of wood cut from the larger limbs that were removed during pruning. Getting things ready for the coming season.
A horticultural oil spray, also known as dormant oil, will be the next step. Dormant oil refers more to when it should be applied, i.e. dormancy, when the tree’s active growth is suspended. Things would be simple if year after year we could mark our calendar and follow this same schedule. However, there is no set schedule to follow as varying weather patterns will create different situations. The goal to spraying is prevention. The orchardist sprays to prevent disease and not cure disease. After the fruit is damaged, the fruit cannot be healed, no matter what chemical applications are sprayed or how heavily those chemicals are applied.
Newer dormant oil formulations are typically refined from petroleum oil such as mineral oil. The formulation contains an emulsifier to help water mix with the oil thus providing a better and more complete coverage of the plant surfaces. Dormant oil is not harmful to pollinators and safe for human ingestion. There is no toxic residue and the spray dissipates quickly.
Dormant oil covers leaf and limb surfaces, suffocating insects and some insect eggs which reduce harmful insect infestations. It may also interfere with insect feeding. Dormant oil is one of the most important and effective sprays to apply. We were advised by an entomologist that if only one spray was applied during the season, it should be dormant oil. That’s how important it is to the orchard. It controls a variety of insects such as aphids, mealybugs, thrips, whiteflies, caterpillar eggs, leafhoppers, scale and mites.
When applying any spray, be sure you understand the purpose of the chemical you are using and ALWAYS follow the manufacturer’s recommended usage rates. All spray materials have label instructions and please read all labels carefully. Any spray can be harmful to health and the environment if it is misused.