HARDINESS: Zones 4 to 8
PREFERRED SOIL pH: Near neutral
PREFERRED SOIL TYPE: Moist, fertile, well-drained
PREFERRED LIGHT: Partial shade
ATTRIBUTES: Purple, silver, or marbled foliage; salmon to red flowers; for beds, pots
SEASON OF INTEREST: Spring to fall
FAVORITES: 'Palace Purple', 'Persian Carpet', 'Mt. St. Helens', 'Raspberry Regal'
QUIRKS: Grows poorly in hot sun or dry soil
GOOD NEIGHBORS: Euphorbia, hosta, lamb's ears, meadow rue
WHERE IT GROWS BEST: In partial shade and moist, well-drained soil
POTENTIAL PROBLEMS: Shallow roots can be heaved up in winter
RENEWING PLANTS: Lives to 5 years; divide every 3 years, before plants become woody
CRITTER RESISTANCE: Deer, strawberry root weevil
SOURCE: Bedding plants, division
DIMENSIONS: 1-3 ft (0.3-1 m) tall, 1-2 ft (0.3-0.6 m) wide
Heuchera in the Landscape
The most difficult thing about these versatile garden standouts may be pronouncing their name: HEW-ker-a. Although their ancestors are humble native plants from both eastern and western regions of North America,
modern garden heucheras are anything but plain. Showy hybrids often have deep red-bronze evergreen leaves marked with purple, such as the award-winning 'Palace Purple", or silver, such as 'Persian Carpet'. Others, which are suitable for sunnier spots, have green leaves marbled with white and sometimes blushed with pink.
All heucheras produce airy flower spikes studded with tiny bell-shaped flowers in early summer. The flowers are pale and spindly on most dark-leaved cultivars, so many gardeners simply snip them off. But keep the snippers sheathed if you choose varieties bred to live up to their common name of coral bells. These heucheras, including 'Mt. St. Helens' and 'Raspberry Regal', are crowned with wiry, 20 in (50.8 cm) flower stems heavily laden with abundant salmon to deep red miniature bells that persist for weeks. After the flowers fade, snip out old stems to encourage an encore.
To prod heucheras to really strut their stuff, give them exactly the right amount of light. Dark-leaved varieties scorch quickly when forced to bake in hot sun, so they are best grown in beds that get no more than 4 hours of direct sun. In shade gardens, where white-variegated plants are often prominent, dark-leaved heucheras provide incomparable contrast.
Heucheras that have green leaves can tolerate more sun, but they still may suffer, so monitor their welfare and move them to a shadier spot if leaf edges appear curled and dry at the end of a hot summer day.
Light-textured, quick-draining soil enriched with compost is ideal for heuchera. In soggy soil, these cliff-dwelling natives can succumb to root rot. Set container-grown plants at the same depth at which they were growing in their pots. Fill the hole around the root ball, firm the soil with your hands, and water well. Never allow heucheras to dry out completely or growth will come to a screeching halt.
Heucheras have shallow roots, a trait that can make them heave out of the ground as it freezes and thaws in cold-winter areas. To prevent this, cover them with a fluffy mulch of evergreen boughs after the soil freezes hard. In climates where the soil does not stay frozen all winter, check plants several times and gendy push them down if they seem to be popping out of their places.
Dig and divide heucheras every 3 years in late winter or early spring. Dig up the clump and use a sharp knife to cut it into 4 sections. Pick away dead material with your fingers, and then immediately replant the divisions where you want them to grow. Heucheras are for the most part pest and disease free.
Heucheras are related to strawberries and can fall prey to strawberry root weevils. The adults chew holes in the leaves, and the larvae eat the roots. Apply beneficial nematodes to the soil according to package direction in midspring to control the larvae, which can reduce healthy plants to tumbleweeds. Hungry deer may also nibble the plants. If you find that leaves have been neatly nipped off, tuck a bar of deodorant bath soap into die planting to repel deer or purchase a commercial repellent.