Culture
Best grown in organically rich, humusy, medium moisture, well-drained soils in full sun to part shade. Performs well in full sun in cool summer climates, but prefers some shade (particularly in the heat of the afternoon) in climates with hot, humid summers. Can tolerate occasional, short periods of drought, but foliage appearance may depreciate. If grown in full sun, consistent moisture is particularly important. Remove stems of faded flowers to encourage additional bloom. Foliage is essentially evergreen in warm winter climates, but the amount of retained foliage color in cold winter climates depends in large part upon the severity of the temperatures. In cold winter climates, a winter mulch applied after the ground freezes will help prevent root heaving. Divide clumps in spring every 3-4 years.
Noteworthy Characteristics
Heuchera americana, commonly called coral bells or alumroot, is a clump-forming perennial native to much of eastern and central North America. It is typically found in rich woods over calcareous substrate, rocky open woodlands, along ledges and crevices of bluffs or rock outcrops, and occasionally shady roadsides. Typically features a 12-15" tall basal clump of heart-shaped, 5- to 7-lobed, long-petioled leaves (3-5" wide), which emerge flushed with purplish-brown and mature to a uniform green. Tiny, greenish-white, bell-shaped flowers in open, airy panicles are borne on slender, wiry stems extending well above the mound of leaves, typically to a height of 18-24" (infrequently to 3') in late spring to early summer.
Genus name honors Johann Heinrich von Heucher (1677-1747), physician, botanist and medicinal plant expert at Wittenberg University, Germany.
Specific epithet means of the Americas.
'Marvelous Marble Silver' is a compact selection of alumroot that features a mounding basal rosette of silver tinted foliage with contrasting, dark green veins. The foliage emerges with shades of purple that fade to green as the season progresses. Mature clumps will reach up to 8" wide and 12" tall. Airy panicles of small, white flowers bloom in mid-spring and are held on wiry stems around 12" above the foliage clump.
Problems
No serious insect or disease problems. Frost heaving of roots may occur when winter temperatures fluctuate widely.
Uses
Attractive foliage and airy flower panicles provide color and contrast to the rock garden, perennial border, native plant garden, open woodland garden or shade garden. Good edging plant. Mass to form an attractive ground cover.