Serving the Okanagan Valley since 1971


The following is a general guideline regarding when to spray for certain insects. Click here for a general overview of optimum spraying schedules.

Spring/Fall Dormant Oil for Fruit/Tree/ Shrubs/ Shade trees

Oil based insecticides were developed for use during the dormant season, before the flower buds begin to open. This "dormant oil" kills off overwintering insects such as aphids, mites and scale, by virtually suffocating them because the oil blocks the spiracles through which insects breath. Having used dormant oil for many years, we have found it quite successful at reducing the insect population and have noticed that yards without treatment of dormant oil do appear to have more insects.

February - Peachleaf Curl - affects peaches and nectarines

Peachleaf Curl is a fungus disease which appears in the Spring, when there has been prolonged wet weather at the same time as the new growth is developing. Infected leaves become thick, curled and discoloured, and eventually drop. Heavy leaf infection and subsequent leaf drop may reduce crop.

April/May - Leafroller affecting Fruit Trees

Leafrollers overwinter as eggs which begin to hatch at the pink bud stage of apples. Larvae are green with black heads and feed upon buds, leaves and fruit. Early season feeding on apples and pears causes deep russeted scars on mature fruit, and malformation and pitting on cherries.

April - Peach Tree Borer affecting Peach, Apricot, Nectarine, Plum and occasionally Cherry trees

Peach, apricot, nectarine, plum and occasionally cherry trees are attacked by these pests. Masses of gum mixed with sawdust and frass near the soil line of the tree trunk indicate borer damage. The removal of this gum and bark around damaged areas will reveal feeding tunnels and cream-coloured larvae wtith brown heads. Young trees may be girdled by larval feeding while larger trees are weakened and therefore susceptible to attack by secondary pests, including shothole borer and ambrosia beetles.

June - Cherry Fruit Fly affecting Cherry Trees

In the Okanagan Valley, cherry fruit flies begin to emerge from pupae in the soil in early June and continue to emerge throughout August. The flies begin laying eggs under the skin of the cherries when the fruit first starts to turn from blush to red in colour. White legless maggots bore out of the cherries, drop to the ground, and pupate near the surface of the soil. There is one generation each year, although a small percentage of the flies may produce a second generation.

June to August - Codling Moth affecting Apples, pears, flowering crab quince

Codling moths infest apples, pears, flowering crabapples and quince. Codling moth injury is characterized by holes in the fruit, which are plugged with frass. Codling month larvae are white with black heads in early stages, and pink with molted brown heads when mature. Adults are small grey moths with a copper spot at the tip of each forewing. First brood moths appear in late May to early June, and second brood moths in late July to early August. Codling moth activity depends on the weather, with temperature the principal factor. Timing of the first spray is very difficult to determine because of the variable weather conditions in May and June, therefore we at Olson's Pest Control work closely with government trapping programmes to determine the best time to spray.

Check out Olson Pest Control's yearly schedule for best times to spray your fruit trees.

Consistent spraying schedules will help keep your fruit trees in great shape for years to come.