Drought- and Heat-Tolerant Annuals
End your affair with the garden hose by filling your garden with drought-tolerant annuals. These beautiful bloomers beg for attention—but not in terms of care. They fill the garden with traffic-stopping color just about the time spring flowers fade and fizzle. Add heat-tolerant annuals to your landscape and you’ll savor summer as you survey a yard filled with colorful flowers.
Drought-tolerant annuals won’t guzzle water once they’re established—but they do need regular irrigation after planting. Until plants are consistently unfurling new leaves, keep soil moist. Aim to give a weekly deep watering, but always check soil first to make sure it needs watered. In containers, of course, even drought-tolerant annuals need regular irrigation.
Add a mulch layer to enhance the drought tolerance of your plantings. Put down 2 inches of mulch in northern regions and up to 3 inches in southerly locales. Many gardeners opt for a gravel or stone mulch with drought-tolerant annuals. Just realize that gravel does retain heat and radiate it to plants at night, so stick with heat-tolerant annuals in gravel mulched beds.
The list of drought-tolerant annuals and heat-tolerant annuals overlaps and includes a host of brightly-tinted bloomers. You won’t lack for color when you create a low water use landscape that thrives in summer heat. Start with the low-growing moss rose (Portulaca grandiflora). This drought-tolerant annual has fleshy, succulent-like leaves that hoard water. Flowers open in a rainbow of cheery hues with a rose-like appearance. Many types happily self-seed and form a self-sustaining ground cover on a gravel bed.
Gazania also has a somewhat succulent leaf form that stores water. Like moss rose, gazania blooms open in full sun and remain closed on cloudy days and overnight. In the landscape, gazania is a heat tolerant annual that needs little care. You don’t need to add water or fertilizer to keep this plant looking its best. Flowers come in many hues and bicolor combinations.
Globe amaranth (Gomphrena), celosia and ageratum (Ageratum houstonianum) offer both heat and drought tolerance. All have distinct flower forms that add fantastic texture to garden plantings. Plant the tall hybrids of globe amaranth and ageratum, along with tall verbena (Verbena bonariensis) and gloriosa daisy (Rudbeckia hirta), and you have the makings of a cutting garden that can fill vases all summer long.
All of the heat-tolerant annuals mentioned also beckon butterflies. Plant them with lantana, melampodium (Melampodium divaricatum) and marigold to have a strong butterfly garden that won’t demand intense care as summer temperatures soar. Add zinnias, especially the Profusion types, and you’ll have even more butterfly-luring color.
Summer snapdragon (Angelonia) is another heat tolerant annual that holds its own, even in Texas summers. The Serena types offer a lower price point as bedding plants because they’re grown from seed. Vinca (Catharanthus roseus) is sometimes called Madagascar periwinkle. New types grow in a trailing formation that quickly covers ground in the garden.