We’ve had some stellar weather for the last week and I have to wonder, “Are the plants that I’ve put in going to be safe, or is there a killing frost lurking around the corner?” Historically, I have put in plants – as have many, many of us – only to have them frosted because I’ve been faked out by Mother Nature. How are all of you feeling about this weather? Solid spring or Mother Nature’s fake-out?
- Prepare and prime irrigation system for summer.
- Use a soil thermometer to help you know when to plant vegetables. Wait until the soil is consistently above 70°F to plant tomatoes, squash, melons, peppers and eggplant.
- Place pheromone traps in apple trees to detect presence of codling moth. Plan a control program of baits and/or predators when moths are found.
Maintenance and Clean Up
- Fertilize rhododendrons and azaleas with acid-type fertilizer. If established and healthy, their nutrient needs should be minimal. Remove spent blossoms.
- When selecting new roses, choose plants labeled for resistance to diseases. Fertilize roses and control rose diseases such as mildew with a spray of water/baking soda/a bit of oil.
- Plant dahlias, gladioli, and tuberous begonias.
- Plant chrysanthemums for fall color.
- Plant these vegetables: Snap and lima beans, Brussels sprouts, cantaloupes, slicing and pickling cucumbers, dill, eggplant, kale, peppers, pumpkins, summer and winter squash, onions, potatoes, tomatoes, and watermelon.
Pest Monitoring and Management
- Manage weeds while they are small and actively growing with light cultivation or spray with white vinegar.
- Trap moles and gophers as new mounds appear. Or get a nice, big cat.
- Leaf rolling worms may affect apples and blueberries. Prune off and destroy affected leaves.
- Monitor aphids on strawberries and ornamentals. If present, control options include washing off with water, hand removal, or insecticidal soaps. Promoting natural enemies (predators and parasitoids that eat or kill insects) is a longer-term solution for insect control in gardens.
- Spittle bugs may appear on ornamental plants as foam on stems. In most cases, they don’t require management. If desired, wash off with water or use insecticidal soap as a contact spray.
- Control cabbage worms in cabbage and cauliflower, 12-spotted cucumber beetle in beans and lettuce, maggot in radishes. Control can involve hand removal, placing barrier screen over newly planted rows, or spraying with insecticidal soaps.
- Tiny holes in foliage and shiny, black beetles on tomato, beets, radishes, and potato indicate flea beetle attack. Treat with Neem, Bt-s, or use nematodes for larvae.
- Prevent root maggots when planting cole crops (cabbage, broccoli, collards and kale), by covering with row covers or screens.
- Monitor rhododendrons, azaleas, primroses and other broadleaf ornamentals for adult root weevils. Look for fresh evidence of feeding (notching at leaf edges). Try sticky trap products on plant trunks to trap adult weevils. Protect against damaging the bark by applying the sticky material on a 4-inch wide band of poly sheeting or burlap wrapped around the trunk. Mark plants now and manage with beneficial nematodes when soil temperatures are above 55°F. If root weevils are a consistent problem, consider removing plants and choosing resistant varieties.
- Control slugs with bait or traps and by removing or mowing vegetation near garden plots, plates of beer or diatomaceous earth.
- Identify problems before acting, and opt for the least toxic approach. Cultural, physical and biological controls are the cornerstones of a sustainable pest management program. Least-toxic choices are insecticidal soaps, horticultural oils, botanical insecticides and organic and synthetic pesticides and natural predators.
If you are having issues with a specific plant, need help identifying a problem or pest, do contact the fine folks at the extension offices:
Southern Oregon Research & Extension Center
569 Hanley Road, Central Point OR 97503
Josephine County Extension Center
215 Ringuette Street
Grants Pass, OR 97527