It is tough to get enthusiastic about a fall garden during the oppressive heat and humidity in July and August. That aside, there is plenty to do in the garden during summer doldrums, especially if you want to finish out the summer with a good-looking yard and then enjoy a productive fall gardening season.
In hot temperatures, flower colors fade, and blooms have a shorter life. If plants are burnt to a crisp from the heat and sun, pull them out. Otherwise, continue to deadhead spent flowers and trim off ripening seeds to keep new flowers coming. Groom ragged and leggy plants. Cut back annuals to encourage new growth and bushiness. Remove unattractive yellow and brown leaves for a much tidier look. Prune roses (back to an outward-facing node) to get rid of Japanese beetle damage.
Fertilize freshly pruned annuals as well as fall-blooming perennials like chrysanthemums, dahlias, cannas and salvia. Select an organic fertilizer because the high salt content of chemical fertilizers is more likely to burn plants in high heat than organic counterparts. Do not fertilize azaleas, camellias and summer-blooming shrubs.
If your irises have ceased to bloom, do not try to solve the problem by giving them extra fertilizer. It is likely they do not get enough sun, the rhizomes are overcrowded underground, or they are planted too deeply. Irises should be planted in a spot that gets at least 6 to 8 hours of sun daily. The top of the rhizome must be exposed – not below ground – and lightly covered with mulch. Make sure they have regular water and good drainage. Separate and transplant irises during August.
You have heard it before. If you want unusual or special spring-blooming bulbs, order them early because the most desirable ones sell out quickly. Keep the bulbs in a cool dry spot until you are ready to plant them in November or December.
Invite butterflies into your yard by creating spots for them to puddle. Fill a shallow dish with soil and water, making a watery mud. Add a few stones that rise above the mixture. Place the dish near their favorite flowers. Butterflies will gather, perch on the stones and drink water from the mix.
Some summer vegetables will continue to produce. Fertilize them with low nitrogen fertilizer. Remove those at the end of their production cycle. Declining plants attract insects and disease.
Prepare for your fall garden by adding compost and organic fertilizer to your soil. Spring supplements are likely substantially depleted.
You can start flowers like alyssum, amaranthus, calendula, cosmos, cleome, nasturtiums and zinnias from seed for low-cost color in your fall garden. You will provide food for the bees and hummingbirds, too.
Herbs like basil, dill, chives, marjoram, oregano, fennel, parsley and sage also grow well in the fall.
Google Clemson hgic 1256 for a planting chart that lists vegetables and planting dates for each region of South Carolina. For tender crops like tomatoes, peppers, cucumbers and eggplant, choose varieties that mature quickly. Root crops like carrots and beets can stay in the ground until well after the first frost.
Starting seeds in hot summer sun and soil requires some special attention. Sow them a bit deeper than usual in a spot protected from direct sun. They need to be kept constantly moist to succeed. Once they are strong with a good root ball, slowly accustom them to direct sun before planting them in the ground. Warm soil then provides a good environment for plant growth.
Newly planted shrubs and trees need extra water during extended hot, dry weather until they become established – usually a year for shrubs and 2 to 3 years for trees. Keep first-year perennials well-watered, too.
Don’t ignore weeding. Weeds steal water and nutrients from desirable plants. They also produce thousands of seeds, which will plague you and your neighbors in future years.
Turn over mulch and freshen it. Remember, it moderates soil temperature and helps the soil retain water, both of which are particularly important to plants during heat and drought.
Reach DEBBIE MENCHEK, a Clemson Master Gardener, at email@example.com.