Spraying fruit trees

Asked November 3, 2017, 5:38 AM EDT

I have pluots,apple,plum,permission, cherry,jujube,fig trees. How often does OSU suggest to winter spray and what months. Is there a particular winter solution you suggest.

Josephine County Oregon pesticides fruit trees horticulture

2 Responses

Generally for all deciduous trees it is beneficial to give them 2-3 dormant sprays each winter. The first spray for your trees should go on around Thanksgiving when at least 50% of the leaves have fallen off. If you make dormant sprays with more leaves on trees than that, you wont get great coverage on all the branch surfaces. Homeowners can usually find a copper fungicide for that first spray. The second spray should go on after you have pruned your fruit trees in late January. I like to use either Lime-Sulfur or Copper again. If you have the time and especially if your trees had much disease, I like to make a third spray right when the buds begin to swell which is usually in late February or early March in Douglas County. Don't wait until the buds have enlarged a lot or opened or many pathogens wont be controlled.

I have found over the years that some fruit tree crops don't need as many sprays as others. The stone fruit family requires all three sprays as do the pears and apples. Figs, persimmon, and jujube are less prone to disease and pests so they can get by with one spray.

I forgot to mention dormant oil sprays. Overwintering insects can often hide in the bark of trees or lay eggs on the tree branches. It is a good idea to make at least one dormant oil spray during the winter. You can include the oil in the spray tank when using fungicides but be careful with young trees that have thin bark. I generally think it is better to make a separate spray in January with oil instead of the second fungicide spray if you are limited with time. I try to make the oil spray at least two weeks away from any fungicide spray especially with young trees under about 7 years old.