For gardeners, August means one of two things depending upon where you live — it’s either hotter than blazes with another month of the same, or it’s the gateway into fall gardening. Whichever one applies to you, it translates into “there’s a whole lot to do in August,” so get out your garden gloves and let’s get to work!
As always, we suggest consulting your local extension office or a trusted garden center for more precise planting suggestions for your area — areas within the same zone can have a number of different microclimates, making a one-size-fits-all garden calendar impossible.
Gardeners in these zones experience a bit of relief in August with cooler mornings and less intense heat during the day. In the northernmost areas, this month is more about harvesting and preparing rather than active planting. Go ahead and seed your wildflowers and fall veggies, and order trees, shrubs, and spring-blooming bulbs for fall planting.
Prune summer-blooming shrubs (hydrangea, caryopteris, clethra) after they’re done blooming, and plant garlic for spring harvest. Dig up, divide, and transplant overgrown perennials.
Keep harvesting your late summer veggies to encourage more production, and harvest herbs to dry for cold season cooking. Begin moving patio plants, tropical plants, and other tender potted perennials indoors to acclimate, and build or buy a cold frame to extend your harvest. Love planting bulbs? Prepare those beds now for fall planting!
Gardeners in these zones are using swear words right about now, as August can produce some of the most brutally hot weather around. This means if you’re sweating in the heat, think about how your garden is feeling! To help it along, continue watering deeply rather than frequently, always observing any watering restrictions your area has in place.
Start sowing seeds for your fall garden, and plant a final round of okra, squash, peppers, tomatoes, and beans. It’s also time to get those Irish potatoes, broccoli, Brussels sprouts, collards, and onions in the ground. Prune dead or broken tree branches, but wait until the dormant season to complete any major pruning.
Trim back spring-planted annuals that have gotten leggy, and remove spent flowers from perennials to encourage a new flush of blooms. Continue to watch for warm-season pests like chinch bugs, borers, aphids, and webworms, staying on top of treatment to avoid severe damage.
Gardeners in zones 9-11 are so used to hot weather that this month is just a normal walk in the park. As with zones 6-8, continue watering deeply to encourage healthy roots and drought tolerance. Water most container plantings daily, and fertilize regularly for best blooming.
Keep a 2”-3” layer of mulch in garden beds to conserve moisture and suppress weeds. Start seeds of Brussels sprouts and cabbage indoors, and get those sweet potato, potato, eggplant, and pepper transplants in the ground now. Harvest celery, eggplant, peppers, beans, corn, melon, and the last of your cucumbers this month as well.
Remove dead, damaged, or diseased wood on trees as soon as you observe it, but save major pruning for the dormant season. Raise the height of your mower blade to 1” – 1 ½” to help your lawn thrive in the late summer heat. Gardeners in areas prone to hurricanes should be prepared to protect their gardens as needed.