Popular vegetables such as tomatoes, beans, cucumbers and squash generally need warm but mild daytime temperatures in the 70s and 80s to produce well. The scorching heat that we experience in midsummer lowers the production of these vegetables by reducing the number of flowers that set fruit. In addition, high populations of many pests, such as spider mites, leaf miners, beetles and caterpillars, are present now and will cause increasing amounts of damage through the summer.
Once they are past their prime and production dwindles, remove early-summer vegetables and replant your garden with a wonderful selection of vegetables that thrive in midsummer heat. The LSU AgCenter recommends a wide variety of vegetables that can be planted now. Most of these vegetables are near and dear to Southerners and form an important part of our regional cuisine.
Native to tropical Africa, it never gets too hot for okra to thrive here. Direct-seeded into the garden now, okra will come into production in late August or early September (sooner if you plant transplants) and produce until the weather cools in late October or early November. Reliable varieties include Clemson Spineless, Cajun Delight, Louisiana Green Velvet, Emerald and Burgundy.
A common mistake gardeners make is growing the plants too close together. Once the okra seedlings are a few inches tall, they should be thinned to 12 inches between plants. When the plants are about knee high to waist high, they begin to produce their pale yellow, hibiscus-like flowers. Harvest okra pods frequently when they reach a length of about 3 inches for best quality, although some varieties stay tender if harvested larger.
Unlike their relative, tomatoes, eggplants thrive in the heat of mid- to late summer. Purchase transplants to plant into the garden now. I have generally found the oriental types such as Ichiban or Tycoon with long, narrow fruit are especially productive during stressful summer weather. Large-fruited varieties such as Blackbell, Classic, Midnight and Florida Hi Bush as well as green, white, lavender and pink varieties are also recommended.
Plant transplants 18 to 24 inches apart in well-prepared beds. Production should begin in early September and increase through late October or early November.
Do not go by the size of the fruit when harvesting eggplants. Eggplants are eaten immature and should not be allowed to become old and bitter before harvest. The skin should be shiny and tender. Once the skin starts to dull, you should harvest the eggplant immediately, no matter what the size, because it is getting past its prime.
Although it is too hot for reliable production from legumes like snap beans and lima beans, Southern peas such as purple hulls, crowders, cream peas and black-eyed peas produce abundant crops during the summer. Direct-seed them in rows about 18 inches apart and thin young seedlings to stand 4 to 6 inches apart.
Most varieties produce short, somewhat bushy vines and do not require a trellis to grow on. Other legumes that could be planted now include yard-long beans, winged peas (these need trellises to grow on) and edible soybeans.
Bell peppers often produce poorly during high temperatures, but hot peppers and sweet peppers such as Sweet Banana, Gypsy and Pimento produce very well despite the heat. Plant transplants now spaced about 18 inches apart. Bell pepper transplants can be planted now through August for production this fall when the weather cools down.
Spring-planted tomatoes are about finished with their main crop, and if the plants are in poor condition, they should be removed to make way for heat-tolerant crops. Cherry and Roma types may still be producing well and could be left in place.
If you want to grow your own transplants for fall tomatoes, plant seeds now. Transplants for fall tomatoes will be available at area nurseries in late July and August and should be purchased and planted into the garden then. Good varieties for fall production include Hawaiian Hybrid, Solar Set, Heatwave, Bingo, Celebrity and Pelican.
Other heat-tolerant vegetables that may be planted now include cantaloupe, pumpkin, watermelon (these three are a bit of a challenge in the home garden), peanuts (easy to grow and a great crop for kids) and sweet potatoes (plant rooted cuttings or “slips” as soon as possible for harvest in November).