The original 'Purple Palace' discovered in a palace in England is believed to be a "H. micrantha" × "H. villosa" hybrid, which was then crossed with "H. americana". Another group of hybrids are crosses of "Heuchera" with "Tiarella" treated under the name × "Heucherella". Gardeners and horticulturists have developed a multitude of hybrids between various "Heuchera" species. There is an extensive array of blossom sizes, shapes, and colors, foliage types, and geographic tolerances. They are valued as foliage plants, producing rosettes of leaves in shades of green, pink and bronze, often variegated or textured; with long thyrses of white, green, pink or red flowers in spring.