Whether you say HUE-ker-uh or WHO-ker-uh, one of the easiest native plants to ease into a mixed suburban garden is Heuchera, also known as alum root or coral bells. The evergreen perennial clump, a foot or two high, has grapelike leaves topped by slender, frothily flowering stems in the spring. A few varieties have flowers that last into summer or fall.
Like most natives, they need good drainage to avoid root rots. So if your soil is clay, plant them in mounds. Most varieties grow best in light shade or dappled shade, or at least with afternoon shade, so they're ideal around the driplines of trees. They can even be grown under redwoods, where with good drainage they're tolerant of occasional to regular water.
Smaller heucheras look lovely bordering paths in part shade, where the clumps form a neat informal edge and the flowering stems add seasonal drama.
If you want a few container plants as accents in shadier corners, heucheras adapt well to container culture, where they will need to be watered a couple times a week. Place them near a window so you can watch hummingbirds visiting the flowers.
Planted in garden beds with other perennials, heucheras stand out when their white, pink, or red flowers are in bloom, especially when planted in massed groups.
The 2-foot-wide clumps of island alum root, Heuchera maxima, are decorative in themselves, with scalloped-edge 4-inch roundish leaves, green with lighter marbling, rising from the base. But in spring, profuse clouds of creamy flowers appear on spikes a foot or two above the foliage, suggesting snow drifts. The largest member of the clan, island alum root tolerates clay soil better than other heucheras and can flower in denser shade than other varieties. As a groundcover under native oaks, it thrives in high dappled shade and is drought tolerant.
Hairy alum root, Heuchera pilosissima, is reputed to be deer-resistant because its leaves are covered with less-palatable white hairs. Its white flowers age to pink.
The most colorful heucheras are named cultivars, many of them half-native hybrids with Arizona's native coral bells. In general, they're half the size of island alum root, have a longer bloom season, and need occasional to regular garden water, and a few can tolerate a little more sun. Flower colors of some of the more popular varieties are pink 'Wendy', red 'Santa Ana Cardinal', magenta 'Canyon Belle', apricot-pink 'Chiqui', and pink 'Martha Roderick'. Leaf colors and patterns vary as well: 'Painted Lady' has silver marbling and a purple reverse, 'Genevieve' has gray marbling.
With age, the crowns grow up and out of the soil, and the thick leaf stems elongate, so heucheras will need to be divided every three years or so in the spring or fall. When you notice your plants are getting smaller and less vigorous with fewer flowers, all you do is dig up the whole plant, cut apart the stems branching off the main woody stem, and plant them separately with at least 2-3 leaf nodes underground. If the stem pieces do not already have roots, plant them in containers with a soilless mix and keep moist until they root.
© 2010 Tanya Kucak