Each year representatives of the professional horticulture industry select one perennial to be showcased, chosen because it is popular, easy-to-grow, widely adaptable, genetically diverse, and versatile. Heucheras take top honors in 2012.
You might not be aware that Heucheras are ALL-American. The different species hail from islands off the California coast to the Rockies to the Gulf of Mexico. With this diverse range of habitats, these plants are able to find a niche in everyone’s garden. Breeders in America and Europe are continuously making crosses between the species, resulting in a plethora of hybrids with amazing flower and foliage forms that didn’t exist 10 years ago. These plants are not only pleasing to the eye, but have become stronger, fuller and more disease resistant.
Before the new wave of hybrids, most heucheras claimed a heritage from only one species, H. sanguinea, and were known as Coral Bells. Today, in order to give gardeners stronger, prettier plants, breeders are combining species to provide a mix of outstanding characteristics. Following is a brief primer on some of the major heuchera species and their advantages.
• Heuchera americana likes woodland situations best, survives extreme hot and cold temperatures, offers an exceptionally tidy mounding habit and shows off the most exciting leaf patterns.
• H. villosa varieties, with their hairy, large leaves, are best for the deep South and any other hot, humid climate. H. villosa hybrids are especially popular.
• H. micrantha, a native to the West Coast, tolerates wet roots better than other coral bell varieties. These lend their wavy leaves to any hybrid, ruffled form on the market today.
• H. cylindrica presents a more compact form with strong, rigid flower stems that stand up to windy conditions. These are very attractive to bees and butterflies. This species is not as eye-catching as its more showy sister species due to its green or white blooms.
• H. sanguinea, a Southwestern native, maintains its often-bright blooms through extreme drought and heat. Most do well in shady rock gardens or along woodland paths.
Culture and Garden Preferences
Heuchera require well-drained soil. If you’ve had problems with coral bells in the past, most likely you’ve tried to plant them in soil that’s too wet or full of clay. To solve that, plant your heucheras in raised beds, on a berm, or in containers. Even mounding the soil slightly where you plant them will help. A premium organic planting compost will provide excellent drainage with enough moisture.
Other than keeping the soil well-drained and mulched, coral bells have very few other maintenance needs. Let them dry between watering, refrain from using excess fertilizer, and give them neutral or slightly acidic soil (the perfect ph is 5.8 to 6.3, but most aren’t too fussy).
Many coral bells do well in part sun, but stay away from hot afternoon rays—foliage will often fade, wilt, or scorch under intense sunlight. Instead, provide shade during the hottest times of the day, or plant where your heuchera will get consistent full or filtered shade.
Heuchera are remarkable for needing little care. When flowers fade, they can be spun off with a flick of the wrist. If stems get too long they can be cut off with the resulting stub resprouting and the piece in your hand replanted to form a new plant. This helps keep your heuchera compact.
When using “heuchs” in the landscape, they are best triangulated with most varieties planted 24 inches on center. You will have to look at the spread on the label to determine the best spacing. Three words are essential: drainage, drainage, drainage. Most varieties are drought-tolerant as well.
Note that as coral bells grow, their crowns rise up and out of the soil slightly. Either mulch to protect the crown, or lift, divide and replant. It’s best to divide them every two to three years, with the spring being the best time to do this work.
If necessary, cut back winter-damaged foliage in early spring to make way for new growth. And if you live in a cold climate (Z4), mulch your coral bells in winter, leaving the crowns unburied. Oak leaves are ideal.
For the complete story on heucheras, visit the National Garden Bureau website at http://www.ngb.org/year_of/index.cfm?YOID=31 .