Dormant Spray refers to spraying a plant when the plant does not have any active growth in order to prevent insects and disease. The spray can be applied in the late Fall, Winter, early Spring, or a combination of these times.
When used correctly, dormant spray will kill and prevent more insects and diseases than any other sprays during the year.
Dormant Spray, or Dormant Oil, is a physical insect control, meaning it smothers the insects at all stages of life. The oil also penetrates the waxy layer found on insect's eggs interfering with their ability to hatch.
Just what kind of insects and diseases can you protect your plants from with Dormant Oil? Scale, mites, aphids, leafrollers, tent caterpillars, powdery mildew, coddling moths, mealybugs and whiteflies- just to name a few. Because of the broad scope of insect control you achieve with Dormant Oil, it is vital that you never spray while bees are active.
Timing your Dormant Spray application is essential in reaching maximum effectiveness. To prevent insects and disease you should apply the Dormant Oil during a plants dormant phase or when the plant is no longer growing. For deciduous plants, like fruit trees, this is when they have dropped their leaves. Evergreen plants enter their dormancy in the winter. The ideal temperature for application is between 40° and 70° F. Avoid applying during wet weather, or when rain is expected in the next 24 hours.
Some gardeners like to apply a secondary spray to their plants to ensure complete coverage. This is called a "delayed Dormant Spray" and takes place after there is visible signs of growth on the plant. For most fruit trees this can be done after green tips begin to form on the trees branches. Some fruits and plants prefer to be sprayed even later. Please reference the directions of your Dormant Spray for an exact timeline of when to utilize a delayed spray, as it varies from crop to crop.
So what product should you use? After trying several different brands we have found Bonide's All Seasons Horticulture & Dormant Spray Oil to be the most effective when used correctly. This 3-in-1 product is a self-emulsifying spray oil composed of mineral oil, emulsifier and spreader sticker. Like the name suggests, this oil can be used during all seasons, meaning you can use the same product for dormant spray, delayed dormant spray, and for any other insect control needed during the plants lifecycle throughout the year.