Controlling Diseases & Insects in Fruit Trees
Posted by Grange Co-op on 30th Jun 2015
These sprays are designed to be used while the trees are in their dormant stage. These products are used mainly to control diseases on plants. Four applications are optimal; the most essential of these sprays are the first and last.
1ST - In the fall after leaf drop has begun. 2ND - Approximately the middle of December 3RD - The last week of January or the first week of February 4TH - Just before blossoms open in the spring. Watch your trees closely to determine correct timing for this application. It will vary from year to year, depending upon weather conditions.
SEVERAL TYPES OF SPRAYS ARE AVAILABLE TO PREVENT AND CONTROL DISEASES IN FRUIT TREES:
- LIME SULFUR (available at your local Grange Co-op) is used as a fungicide to control a variety of diseases on pomme fruits (apples, pears, crab apples) and on stone fruits (plums, peaches, nectarines). As per the timing schedule above, lime sulfur should be applied as a dormant season fungicide, but may be used during the growing season as well. As a dormant spray it should be used only when temperatures are above freezing (and when hard freeze is not anticipated within 24 hours), and before leaves emerge in late winter. Growing season sprays can be made after leaves are present, but should be applied only in the early morning or late afternoon to avoid burning. Lime sulfur should never be used on apricots; copper spray is safe and effective on apricots.
- LIQUID COPPER SPRAY (available at your local Grange Co-op). Effective prevention/control of many stone fruit diseases. Follow timing suggested above for cherries, apricots, plums, peaches, nectarines as well as other ornamentals listed on the label.
- LIQUID SEAWEED OR KELP This can be sprayed in late winter through early bud break, and during leafing-out, to control peach-leaf curl, and optimize the vigor of peach and nectarine trees (and many other trees and plants).
ALWAYS PRACTICE GOOD SANITATION AROUND YOUR FRUIT TREES
Clean up fallen leaves thoroughly and prevent weed growth around the base of your fruit trees. *When using dormant spray, don’t forget to spray from the base of the tree out to the drip line. This will reduce the number of disease spores and insect eggs left overwintering near your trees.
SPRAY OIL (available at your local Grange Co-op). The oil sticks to the bark so it won’t be washed off by rain, and smothers any insects or insect eggs that may be overwintering on the tree.
Insecticides can control insects that damage both leaves and fruit. Most infestations can be controlled with Malathion (available at your local Grange Co-op) or one of several organic compounds, such as Pyrethrum (available at your local Grange Co-op). These should be used every 2-3 weeks (please follow label directions). Under most circumstances, this will prevent worms in fruits and aphids on the leaves. *Always wait to spray insecticides until after blossoms have fallen. This will prevent harm to bees.
WITHDRAW ALL SPRAYS AT LEAST TWO WEEKS PRIOR TO HARVEST
*Always make sure to follow all label directions faithfully. For help with specific problems, please come by any Grange Co-op store, and we will be happy to assist you.