Garden News: Some bedding plants can thrive in the heat

Weeks of heat and humidity have put quite a bit of stress on summer flowers.

“Our long warm season, which lasts from May to October, is longer than many annuals can stay attractive,” says LSU AgCenter horticulturist Dan Gill. “After months of blooming in your garden, these plants can just run out of steam in late summer and begin to look tired.”

If you want to boost the color in your landscape now, don’t let the heat stop you. Nurseries have excellent selections of colorful bedding plants that will thrive in whatever heat summer throws at them. These plants come in a variety of heights, textures and colors, and are adapted to grow in everything from moist, shady areas to hot, dry, sunny locations.

“It’s generally worth the investment to plant warm-season bedding plants as late as August, given that these plants will stay attractive until November,” Gill says.

Plants lost to insects or diseases can leave empty spaces in flower beds. But instead of looking at these gaps until fall, you can replace those lost plants now.

Large pots or hanging baskets full of colorful bedding plants can add color to outdoor living areas without the labor involved in getting beds in shape for planting.

If you want to replant, Gill suggests making sure the plants you purchase are healthy and vigorous and have been properly cared for.

“This is not the time of year to nurse struggling plants back to health,” he says. “Start off with the highest-quality plants you can find.”

Consider periwinkle, melampodium, alternanthera, angelonia, blue daze, purslane, portulaca, pentas, torenia, perennial verbena, salvia, sun-tolerant coleus, lantana, zinnia, marigold, gomphrena, cosmos or celosia.

For shady and partly shady beds and containers, choose impatiens, torenia, begonia or coleus. “You’re likely to see other great choices available at the nursery as well,” he says.

LSU AgCenter horticulturist Allen Owings says zinnias and marigolds are two excellent examples of warm-season bedding plants to try from August through the first killing frost.

Zinnias and marigolds are easy to grow from seed, but garden centers still carry transplants in late summer and early fall, Owings says.

“Zinnias and marigolds require low care and provide great satisfaction in the landscape as the long, hot days of summer fade to cooler, shorter days of fall,” he says.

Got a gardening question? Write to GardenNews@agcenter.lsu.edu.