By John Fulton
It seems like quality fruit must be sprayed at the recommended intervals. For apples and pears, we start with dormant oils, these need to be applied before buds swell. Dormant oils are usually needed only every two or three years to provide control of scales and mites. Sure, the populations will build up in the off years, but should remain relatively low if the three-year program is followed. Superior oils are lighter grade oils which won't cause as much burn damage during late spring, or even in-season, use. Superior oils will also provide control of the mites and scales.
The first regular spray of the year is applied when the green tissue is ½ inch out of the bud. This spray for homeowners usually consists of a multipurpose fruit spray (and sulfur if needed for powdery mildew). Multipurpose fruit spray has been re-formulated the last year or two to include malathion, captan, and carbaryl (methoxychlor was eliminated from the old mixture). This same mixture would be used when the fruit buds are in the pink stage (when fruit buds show color). After that, the persistence and consistence pays off as you spray with the same mixture about every 10 days until we get to within two weeks of harvest. In our area, we need to continue spraying this late because of apple maggot and sooty blotch.
This spray schedule will also control borers on apples and pears, if you also thoroughly spray the trunk and main limbs of the trees. On non-bearing, young fruit trees where borers have attacked, you can spray the trunks every two weeks during June and July with a multipurpose fruit spray.
The spray schedule for peaches, nectarines, apricots, and plums varies a little bit. The dormant spray for them uses captan fungicide. This is the only spray that controls leaf curl and plum pockets. The next spray is when fruit buds show color with captan, followed by captan at bloom. When the husks begin to pull away from the base of the fruit we would then spray with sulfur, captan, and malathion. This mix would then be used every 10 days or so to within a week of harvest.
For borers on the peach group, you can spray or paint the trunk only with carbaryl (Sevin) on June 15, July 15, and August 15. We walk a tightrope with the loss of some of the insecticides since carbaryl can cause fruit drop or thinning on the peach group and some apples.