What Greens Grow in a Hot Summer?

Spinach-Like

• Although three warm-weather greens have "spinach" in their common names, none of them are in the spinach family. Malabar spinach (Basella alba), a perennial in U.S. Department of Agriculture (USDA) plant hardiness zones 7 through 11, is a heat-loving plant that typically is grown on a trellis. Its leaves are mild in flavor and can be used in any dish that calls for spinach. New Zealand spinach (Tetragonia tetragonoides) is a warm-weather annual that is considered as attractive as it is tasty. New Zealand spinach isn’t as simple to care for as Malabar spinach, but it can be grown in containers. Okinawan spinach (Gynura bicolor) is a low-maintenance, small shrub that thrives in humid areas but also tolerates arid conditions. Okinawan spinach is hardy in USDA zones 8 through 11.

Lettuce

• Batavian lettuce (Lactuca sativa), also known as summer crisp, is the cure for the summertime craving for a fresh-from-the-garden salad. Although it can be grown as a cool-weather crop, it handles summer’s heat just fine. No lettuce seed, however, germinates in soil temperatures higher than 85 degrees Fahrenheit. So it’s important to get the seeds into the ground before the hottest part of summer and keep them in shade while they germinate. Colorado State University tested Batavian lettuces and recommend “Sierra,” “Tahoe,” “Nevada” and “Rouge de Grenoblouse” varieties.

Purslane

• Some people know it as a weed, but greens lovers know the tasty crunch purslane (Portulaca oleracea) imparts when mixed with salad greens. Fond of both hot weather and drought, purslane is the quintessential summer green. It is used in salads, takes well to stir-frying and it helps to thicken soups. Grow purslane in a site that receives full sun exposure, and water it every week or so; it is somewhat drought-tolerant. Although purslane is an annual, it reseeds prolifically, so it will return next season when the weather warms.

Amaranth

• Vegetable amaranth (Amaranthus spp.) is another leafy green that thrives in heat. Its seeds won’t germinate unless the soil temperature is at least 59 degrees Fahrenheit, and they germinate in only three or four days when the soil temperature is at least 68 degrees Fahrenheit. The plant thrives when daytime air temperatures are between 86 and 95 degrees Fahrenheit and nighttime temperatures remain between 73 and 82 degrees Fahrenheit. All amaranth species' foliage contains vitamin A, vitamin C and minerals, but the plants tend to hold nitrates in their foliage. So don’t consume the plants unless you grow them organically.