By Laurel Aiello | Fort Collins Nursery
Do the dog days of summer have you feeling a little drained? If so, just think about your outdoor plants baking in the August heat. Some are likely stressed, root-bound, and looking, well, not their best.
Luckily, there are many plants that can handle consecutive days in the high 90s and even the low 100s in full sun. If you’re looking to refresh your annual pots, hanging baskets, and garden beds, you can find these heat lovers at your local greenhouse.
Zinnias
Zinnias don’t just tolerate high temperatures; they thrive in the hot afternoon sun, producing abundant two-to-four-inch round blooms (up to six-inch blooms for the Benary’s Giant varieties) in stunning shades of red, orange, pink, yellow, and white. Dwarf zinnias make great additions to annual pots since they only grow up to a foot tall, while varieties that exceed a few feet can serve as “thrillers,” adding voluminous height and color to stressed flower beds.
Zinnias are also drought-tolerant, meaning they prefer the soil to dry out a little in between waterings. Encourage new growth throughout the summer and early fall by deadheading spent blooms, and be sure to harvest some at their peak for cut flower bouquets. Like many annuals, zinnias are hungry plants that benefit from regular doses of blooming fertilizer.
Gazania
These heat-loving annuals lend an exotic, daisy-like appearance to the landscape, with beautiful and often bicolored flowers in vibrant reds, yellows, oranges, pinks, and even white. Gazania plants have a mounding growth habit, ranging from six to 12 inches tall and wide, making them great “fillers” for annual flower pots, beds, and hanging baskets that could use a boost of sunset hues.
In addition to high temperatures and full sun, gazanias can tolerate poor soil and little water. Native to southern Africa, they are used to warm, dry climates like ours and will thrive during the remaining hot summer days. Since they have adapted to these conditions, there is no need to fertilize them.
Portulaca
Also called “moss rose,” portulaca is a succulent-like annual with flowers that resemble small roses in bright shades of yellow, orange, red, and pink. They have a trailing growth habit that makes them ideal “spillers” for sunny pots and hanging baskets as well as groundcovers for annual flower beds. Either way, they need room to sprawl.
As their succulent leaves suggest, portulaca thrive in desert-like conditions with full sun, high heat, strong winds, low water, and poor (even sandy) soil—and they don’t need fertilizer. Talk about low maintenance!
Petunias
Several types of petunias have a reputation for being especially heat-tolerant, including Supertunias and Wave petunias. Supertunias come in a wide range of colors (a popular one is the bright pink Supertunia Vista Bubblegum), and they can reach two feet in height and spread even further if given enough room, filling in bare spots that need both a “filler” and a “spiller.” Wave petunias have a similar height and spread, but they also provide unique color combinations such as the Easy Wave mix in red, pink, white, and purple.
Not only do these petunia varieties grow vigorously in hot climates, but they are also “self-cleaning” in that they drop their spent flowers, reducing the need for deadheading. Fertilize them regularly with a bloom-specific formula to enjoy bountiful waves of color until the first frost.