Don’t be discouraged as August’s heat takes its toll on your flower beds. Instead, renovate them for the coming days of fall when the weather will be more hospitable for you and your plants. Continue weeding and deadheading as usual, but put a hold on the fertilizing until spring. Remove tired dying plants suffering from heat, insect, or disease damage.
Your summer annuals are probably feeling the heat. Marigolds may have been severely damaged by spider mites, and some varieties of zinnia may have succumbed to powdery mildew. They can be replaced by cool-season annuals, like coleus, salvia, and petunia. Petunias are one of the best all-around annuals for this time of year. Petunias are actually tender perennials, treated as annuals, so they will hold up and recover nicely even after a light frost. The blue, star-shaped flowers of borwallias make good companions to petunias, especially in containers. Annual phlox, alyssum, and begonia are other annual possibilities for fall color as are many varieties of impatiens.
In the spring, check with garden centers and nurseries to see whether they will be selling any of these annuals in late summer. If not, you may want to start the seed yourself. Also, some annuals are self seeders and spread seed in the garden by themselves, providing you with free additions for fall. Transplant these volunteers to other parts of the garden that need a boost. Before you replace summer annuals with a fall crop, turn under your organic mulch or add some compost to condition the soil.
Some summer annuals don’t need replacing—just a cutting back to get them to bush out and start blooming again. Good plants for this treatment include spring-planted begonia, coleus, annual vinca, and petunia.
Some heat-loving perennials, like blazing star, fernleaf yarrow, false sunflower, and purple coneflower, will be at their peak now – enjoy them in a bouquet for the home. Take note of color, height, and textural combinations in your garden that you might want to change, and notice where perennials are getting crowded. Decide which of those perennials might need to be relocated next spring or this fall when they’re safely past flowering. Volunteer plants may or may not be desired – go ahead and pull the ones that have located themselves inappropriately. Apply compost around the plants for soil improvement.
If you’d like to expand a garden bed, use a garden hose to outline the new curvature of the bed to make sure it’s what you want before you start digging. Also, run your lawn mower around the hose to make sure the new shape can be maneuvered around comfortably at mowing time.
Cool-season veggies can be integrated into your flower beds for interesting color and texture. Lettuce varieties, for example, can be quite ornamental with their variable shapes and colors. Also, consider blending purple cabbage, swiss chard, or attractive greens, like bok choy, into flower beds.
If you are ever needing answers to lawn and landscape questions feel free to call Nancy Olsen, Horticulture Agent, with the North Carolina Cooperative Extension in Bladen County 910-862-4591.