Linn County Master Gardener
OSU Linn County Master Gardener
Warmer temperatures and continuing rain have encouraged new gardens to grow, but also have sprouted millions of dormant weed seeds everywhere. The grasses and other weeds are reaching greater heights too.
It’s important, but time consuming, to try to defeat them before they bloom and go to seed again. Too bad more of us didn’t follow the international trend last year of replacing grass lawns with “no-mow” areas of short evergreen ground covers whose blooms would mean less work as they spread.
Warmer temperatures mean tomatoes and other vegetables will be productively growing now. A side dressing of a balanced fertilizer a month after planting will help them develop successfully.
Watch for insects that also enjoy the 50 to 70 degree F temperature range. Aphids can be washed off leaves and stems with a firm spray of water from the hose.
Lots of little holes in the leaves of young plants indicates flea beetles. Squash beetles and cabbage worms are also competing with slugs for tender plants.
Many of these cannot be seen by day so it is difficult to hand-pick them, so a safe vegetable spray product should be selected such as a pyrethrin-based insecticide. Read the labels carefully and follow the instructions for best results.
Root weevils are feasting and notching azaleas and rhododendron leaves. A sticky trap wrapped on the trunk (about 4 inches) will keep the weevils from climbing up from the soil level to the leaves. Shaking the leaves at night will drop the weevils onto a sheet of newspaper or fabric below. They can then be dumped into a bucket of soapy water – they do not swim.
Planting companion plants that attract beneficial insects will bring in predators that can help control unwanted insect pests.
Spring-flowering shrubs can be pruned to shape after they finish blooming. Trees can still be lightly pruned without harm, but be aware that backyard burning is banned after June 15 in the Canyon.
Consider chipping small wood waste and creating useful mulch that can reduce evaporation of moisture from the covered soil.
Late-summer bloomers like dahlias and gladiolas should be planted by mid-June to have time to grow and produce colorful flowers before fall.
Plan now for practical irrigation during the hot months. Drip hoses use less water and place it at the root zone where it’s needed. Sprinklers allow water to evaporate more in the air and wets the leaves, inviting plant diseases.
To reduce black spot and other diseases, water roses between 10 a.m. and 2 p.m., after the morning dew has dried and allows time for leaves to dry before cooler evening temperatures.
Deep watering (or a good rain) in the morning two or three times a week makes the moisture available in the root zone when plants need to use it on windy, hot or dry days.
To get answers to garden questions call your county extension office, or email your inquiries to “Ask an Expert” from the website https://extension.oregonstate.edu/ .
