Prune Strawberry Runners
Strawberry plants are in very active growth these days, and new runners will proliferate. Remove runners to keep plants spaced according to the method you're using so plants will put their energy into producing future fruit instead of new runners. Left alone, a bed will turn into a mass of foliage and few berries.
Treat for Powdery Mildew
At the first sign of powdery mildew on phlox, bee balm, and other susceptible plants, treat with a homemade fungicide. Mix 1-1/2 tablespoons baking soda into a gallon of water and add 3 tablespoons horticultural oil. Spray plants every two weeks, thoroughly wetting the foliage.
Allow lawn grass to grow higher in midsummer to reduce heat stress. Set mower height to 2-1/2 to 3 inches. This also will reduce germination of weed seeds because they will be shaded by grass blades.
Sow Late Crops
It's not too late to sow lettuce, beets, carrots, radishes, and other short-season crops for a late-summer harvest. Shade lettuce, if possible, during late afternoon to keep young plants cooler, or grow them next to larger plants that provide some shade. You'll need to water more often on these hot days than you did in spring and early summer. Mulch between rows to preserve moisture and block weed growth.
Protect Blueberries From Birds
Birds love blueberries as much as we do, so protect the fruit with netting. Rather than draping the netting over the bush -- birds will still be able to reach the berries -- use stakes to suspend the netting over the shrub. Secure the netting to the ground to prevent birds from sneaking in. Get your cover in place before the berries turn ripe.