Here's your August gardening tips column as we approach autumn.
As always, the Oregon State University Extension Service encourages sustainable gardening practices.
Preventative pest management is emphasized over reactive pest control. Always identify and monitor problems before acting and opt for the least toxic approach that will remedy the problem. The conservation of biological control agents (predators, parasitoids) should be favored over chemical controls.
Use chemical controls only when necessary and only after thoroughly reading the pesticide label. First consider cultural, then physical and biological controls. Choose the least-toxic options (insecticidal soaps, horticultural oils, botanical insecticides, and organic and synthetic pesticides — when used judiciously).
Recommendations in this calendar are not necessarily applicable to all areas of Oregon. For more information, contact your local Extension office at http://extension.oregonstate.edu/find-us
• Optimal time for establishing a new lawn is August through mid-September.
• Dampwood termites begin flying late this month. Make sure your home is free of wet wood or places where wood and soil are in contact.
Maintenance and Clean Up
• Make compost of lawn clippings and garden plants that are ready to be recycled. Don't use clippings if lawn has been treated with herbicide, including "weed-and-feed" products. Don't compost diseased plants unless you are using the "hot compost" method (120 degrees to 150 degrees Fahrenheit).
• Fertilize cucumbers, summer squash, and broccoli to maintain production while you continue harvesting.
• Clean and fertilize strawberry beds.
• Use mulch to protect ornamentals and garden plants from hot weather damage. If needed, provide temporary shade, especially for recent plantings.
• Camellias need deep watering to develop flower buds for next spring.
• Prune raspberries, boysenberries, and other caneberries after harvest. Check raspberries for holes made by crown borers, near the soil line, at base of plant. Remove infested wood before adults emerge (approximately mid-August).
• Monitor garden irrigation closely so crops and ornamentals don't dry out.
• If green lawn is desired, frequent watering is necessary during periods of heat and drought stress. Irrigate 0.25 inches four to six times per week from June through August. Measure your water use by placing an empty tuna can where your irrigation water lands.
• Prune out dead fruiting canes in trailing blackberry and train new primocanes prior to end of month
• Prune cherry trees before fall rains begin to allow callusing in dry weather. This will minimize the spread of bacterial canker.
• Plant winter cover crops in vacant space in the vegetable garden
• Plant winter kale, Brussels sprouts, turnips, parsnips, parsley, and Chinese cabbage.
• Mid-summer planting of peas; use enation-virus-resistant varieties, plant fall crops of cabbage, cauliflower, and broccoli.
• Plant spinach.
Pest Monitoring and Management
• Remove cankered limbs from fruit and nut trees for control of diseases such as apple anthracnose and bacterial canker of stone fruit. Sterilize tools before each new cut.
• Check apple maggot traps; spray tree if needed.
• Control yellowjackets and wasps with traps and lures as necessary. Keep in mind they are beneficial insects and help control pest insects in the home garden.
• First week: If necessary, spray for walnut husk fly.
• First week: If necessary, second spray for peach tree borer and/or peach twig borer.
• First week: If necessary, second spray of filbert trees for filbertworm.
• Check for root weevils in ornamental shrubs and flowers; codling moth and spider mite in apple trees; scale insects in camellias, holly and maples. Treat as necessary.
• Watch for corn earworm on early corn. Treat as needed.
• For mite control on ornamentals and most vegetables, hose off foliage, spray with approved miticide if necessary.
• Check leafy vegetables for caterpillars. Pick off caterpillars as they appear. Use Bt-k, if necessary.
• Continue monitoring peaches, plums, prunes, figs, fall-bearing raspberries and strawberries, and other plants that produce soft fruits and berries for Spotted Wing Drosophila (SWD). If SWD are present, use an integrated and least toxic approach to manage the pests. Learn how to monitor for SWD flies and larval infestations in fruit by researching the many documents that can be found on-line at http://spottedwing.org/ .
• Spray potatoes and tomatoes for early and late blight.