Heucheras are best grown in organically rich, humusy, medium moisture, well-drained soils in part shade. Parentage determines the best culture including optimum sun exposure. Unfortunately, the parentage of many hybrids in commerce today is unknown. Some hybrids will perform well in full sun, particularly in northern climates, but generally prefer some shade in the heat of the afternoon in southern locations. If grown in full sun, consistent moisture is very important. Scorch and general foliage decline may occur if soils are allowed to dry out. On the other hand, some hybrids perform well in shady locations, particularly if H. americana is a parent. Remove stems of faded flowers to encourage additional bloom. Foliage is essentially evergreen in warm winter climates. In cold winter climates such as St. Louis, the amount of retained foliage color in winter depends in large part upon the severity of the temperatures. A winter compost mulch applied after the ground freezes will help prevent root heaving. Divide clumps in spring every 3-4 years. Species plants may be grown from seed, but hybrids are usually divided in the garden.
Heuchera, commonly called coral bells or alumroot, is a genus consisting of about 55 species of evergreen to semi-evergreen herbaceous perennials which are all native to North America. Plants grow in a variety of different habitats including woodland areas, Appalachian seeps, prairies, rocky cliffs and alpine slopes. Plants range in size from dwarf alpine plants with flower spikes rising to only 5” tall to much larger woodland plants with flower spikes towering to 36” tall. Species plants are primarily native to the West, particularly in the Rocky Mountains, with a few species extending into northern Mexico. However, some important species are native to woodland areas in the East and Southeast.
The first significant hybrid heucheras were introduced into commerce around 1980, with the volume of new introductions increasing to almost avalanche proportions in recent years. Hybrids have now supplanted species plants in the marketplace. Species plants most frequently used in producing the hybrids of today are H. sanguinea, H. americana, H. micrantha, H. villosa and H. cylindrica. Leaves of hybrid plants are available in an expanded variety of colors including various shades of green, blue-green, violet, purple, maroon, bronze, silver-black, orange-yellow, yellow, or red, but often with a streaked, mottled or marbled variegation which sometimes includes bold contrasting veins. Flowers of hybrid plants are also available in a variety of different colors including various shades of white, pink, coral or red.
Common name of coral bells is in reference to the red bell-shaped flowers produced by Heuchera sanguina. Common name of alum root is in reference to the medicinal use of some species plants as an astringent to stop bleeding.
Genus name honors Johann Heinrich von Heucher (1677-1746), German physician.
‘Amber Waves’ is a vigorous, clump-forming coral bells cultivar that is best noted for its ruffled, amber leaves. It is the result of a tissue culture of a petiole off a gold leaf found on a Heuchera ‘Whirlwind’. This is a clump-forming perennial which features large, ruffled, amber gold leaves and light rose-pink flowers. Rounded, lobed, long-petioled leaves form a basal mound (to 8” tall) which may spread to 17” wide. Best foliage color occurs in spring. Tiny, very light pink flowers borne in open, airy panicles appear in late spring to early summer on slender, wiry stems rising above the foliage mound (typically to 12” tall). U. S. Plant Patent PP13,348 was issued on December 10, 2002.
No serious insect or disease problems. Frost heaving of roots may occur when winter temperatures fluctuate widely. Potential disease problems include powdery mildew, rust, and bacterial leaf spot. Potential insect problems include weevils and foliar nematodes.
Mass as a ground cover or plant in groups. Borders and open woodland gardens. Effective as an edger along paths or walkways.