In the early spring, the first spray should be applied while the ground and air temperatures are still quite cold. This will be the dormant oil spray, aimed at overwintering insects. Dormant oils are applied on days where the air temperature will remain above freezing for 24 or 36 hours. Read the label for your product. Dormant oils are good in the container for several seasons, so round yours up and see if you have enough concentrate for thorough coverage of all the woody parts of your trees. You may need to purchase more.
The second group of sprays you will need to inventory are those that follow the dormant oil, starting at what we call "green tip," when the overwintering protective bud scales start to soften to allow the emerging leaves and flowers to expand. Most often, these options can be found in your favorite garden center being sold as "home orchard" or "fruit tree" spray, and in combinations to include both insecticides and fungicides so you do not have to buy and store multiple products. Most have a built-in spreader-sticker additive to help the sprays adhere to and spread out across the leaves and fruit for good coverage. Reading the label will help you determine how many gallons of diluted spray you will need for the season. You will use less spray per tree more often at the start of the spray season and more spray per tree but less often as the season progresses to keep the foliage and fruits covered and protected. Those early frequent sprays are going to protect the young leaves and small fruits from diseases, and the later sprays are going on against the late spring and summer insects. No one likes to find a worm in the apple, or worse, half a worm!
Locating your spray equipment should be another part of getting ready for the 2018 growing season. This sprayer should be your dedicated one for the home orchard, one that you have never used for weed control products. Modern sprayers are constructed of plastic and easily cleaned when done.
If your home orchard trees have grown in size, you may benefit from an upgrade in equipment for more capacity, as more spray will be needed for each tree. You will save on how many times you need to fill up, reducing the potential for mistakes to happen if you are filling the tank less often.
Richard Hentschel is a Horticulture Extension Educator with University of Illinois Extension, serving DuPage, Kane and Kendall counties. Stay tuned to more garden and yard updates with This Week in the Garden videos at facebook.com/extensiondkk/videos and the Green Side Up podcast at go.illinois.edu/greensideup. The Kendall County Master Gardener Help Desk resumes for 2018 in March – Monday, Wednesday and Friday from 9 a.m. to 12:30 p.m. at 630-553-5823.