In the Garden | The enemy of my garden enemy

Tim Smith

Organic backyard tree fruit production practices are not much different than conventional practices these days, as science has discovered products and methods that make it possible either way to control key tree fruit pests and diseases of North Central Washington.

The selection of pest management products at the local hardware and garden stores has evolved along with the local fruit industry, and most of the “old-time” products have been replaced with new materials. These new materials often do not stay active on your tree for more than a few days, so must be applied and timed carefully, especially for pests that you can expect to show up almost every year.

Producing fruit safely and effectively is very possible in backyards around here, but if you have a fruit tree in your yard, you have the responsibility to take good care of it. Sometimes, if you value recreation time over gardening chores, it would be best if you removed the neglected tree.

Perhaps the easiest fruit to grow are the stone fruits (other than sweet cherries), such as plums and peaches. Apples and pears are more difficult, with hard-to-manage pests such as codling moth and fire blight, difficult even for professional growers to control.

Before you can manage pests on your fruit tree, you must be able to spray it. Good coverage of an accurately mixed substance is necessary because, organic or conventional, the product must cover the target to be effective.

There are lots of ways to apply the sprays; most are so slow and inefficient that your pest control and patience will suffer. The easier your spraying task, the more likely you are to spray properly and on time. If you have one or two small trees, a simple, 2-gallon air pump sprayer will do the job.

As tree number and size increase, you may be more satisfied with a back-pack, motor-driven air mist sprayer (think leaf blower.) These are expensive, but very effective. The least accurate, in my experience, is the “hose-end” sprayer, which gets as much spray and water on you as the tree.

Mid-winter seems like an odd time to bring up the topic of fruit tree pest control, but in a few weeks we will reach a critical time in the pest management season.

For stone fruits, the “dormant” spray timing, which is just as the flower buds begin to swell, will be here in March. “Delayed dormant,” which is when buds are just opening, also is a timing for sprays to control key insect and diseases of fruit trees. Depending on the weather, that will occur in late March or early April. The first to bloom will be the plums, then the peaches. The peaches and nectarines need a dormant spray before the buds crack open and are infected by peach leaf curl.

I cannot talk about specific materials and rates of spray products in this column, but the WSU Master Gardeners have tree fruit spray recommendation hand-outs that are updated frequently and cover the subject of key pests and the timing of application.


A WSU Master Gardeners of Chelan County column appears weekly in The Wenatchee World. Tim Smith is one of four columnists featured.