Some (plants) like it hot
By Dawn Pettinelli - UConn Home & Garden Education Center
Featured Article - posted Tue., Jul. 9, 2013
As early summer temperatures have really been up there the last few weeks, we aren’t the only ones to wilt from the heat. Many plants - especially young seedlings, recent transplants and those in containers - look rather droopy by the end of a hot day. If continuously stressed by lack of water, plants will perform poorly and, in the case of perennials, trees and shrubs, will affect their survival over the winter.
Small gardens are fairly easy to keep well-watered, but larger areas call for more careful soil preparation and benefit greatly from use of mulch. Pay more attention to plant selection in areas of your yard that tend to dry out the most rapidly. A good number of annuals and perennials tolerate drought periods once they are established. Some actually prefer drier sites.
For really hot, dry sites, consider sedums and other succulents. There are hundreds of different species to choose from. Most are perennials. Some are creeping; others form neat rosettes. The showy sedums such as ‘Autumn Joy’ stand upright at about 18 inches. They have wonderful bright pink clusters of flowers that attract a myriad of butterfly species.
While all succulents bloom, their foliage is also quite noteworthy. Many are evergreen and will color the garden in shades of red, blue, bronze, lime green and chartreuse throughout the year.
Another tough plant grown for its foliage is artemesia. This often rampant species needs room to roam. The familiar ‘Silver King’ reaches 3 feet in height and will quickly fill in dry areas. Stems of silvery-green leaves are often used in wreath-making and for dried arrangements.
Compact ‘Silver Mound’ artemesia forms lacy 1-foot clumps. The foliage of many artemesias is aromatic and they are seldom bothered by insects or diseases.
Yarrow (Achillea) sport bright, flat heads of yellow, red, salmon, pink or white flowers well-suited for fresh or dried arrangements. They are easily grown from seed, although named varieties are vegetatively propagated. ‘Paprika’ has brick-red, yellow-centered flowers and is one of my favorites for hot, dry locations.
Yucca plants produce good-sized rosettes of sharp, sword-like leaves. Clusters of creamy white bells top tall flower stalks in midsummer. There is also a variegated leaf yucca. Another desert-like plant for those who like to grow something different (and probably deer-proof) is the prickly pear cactus. You do need to wear gloves when handling or weeding around the flat, prickly cactus pads. Supposedly it is hardy only to zone 6, but a friend in Massachusetts has a large patch of it which has survived a number of winters.
Many annuals are also quite drought-tolerant once established. For a colorful, low-growing groundcover, portulacas can’t be beat. They survive with minimum water, even seeding themselves into sidewalk and driveway cracks.
Gazanias, with their bright, mostly gold, orange and bronze daisy-like blooms, will brighten up any flower bed. ‘Mini-Star Tangerine,’ which grows to about 8 inches, is an All America Selection winner. Many colorful hybrids have been developed including some silver foliage pink ones. Gazanias will bloom all summer.
Also hailing from South Africa, arctotis is often referred to as the African daisy. The species has creamy white petals with purplish undersides but hybrids come in yellow, white, pink, red and orange. The Ravers Bumble Bee is a Proven Winner selection with buttery yellow, brown-eyed blossoms.
The Madagascar periwinkle, sometimes referred to as annual vinca, has glossy, deep green leaves and flowers in purples, pinks and white. ‘Polka Dot’ is a white selection with a red eye. Although they are quite drought-tolerant, you will get more blossoms if you water them occasionally.
Other drought-tolerant annuals include gomphrena, strawflowers, celosia, marigolds, zinnias and sunflowers. Give these plants a well-drained, light soil and full sun. Water to help them become established, but go lightly on the fertilizer, especially those high in nitrogen.
You can also call for suggestions about other heat-tolerant plants to grow, as well as for other indoor or outdoor gardening queries, toll-free, at the UConn Home & Garden Education Center at 877-486-6271, visit www.ladybug.uconn.edu, or contact your local Cooperative Extension center.