Saxifrage Family – Alum Root or ‘Coral Bells’
Heuchra maxima, Island Alum Root, is native to some of the Channel Islands, where it grows on rocky outcrops and in shady woodlands. It is a tough and beautiful plant and easy in garden culture. In the lowland forests of Northern California Crevice Alum Root, Heuchra micrantha, also grows on rocky outcrops and on steep slopes where deer cannot reach them easily. It is not commonly available and both species need protection from the deer to thrive. In the garden, the alum roots are best grown under deciduous trees where they receive full sun during the colder, rainy season, and shade during the hot summers. Alum roots are also a great plant to grow under the light shade of Coast Live Oaks – perfect also under Valley Oaks!
Heuchras make a real statement when planted in drifts. They bloom freely for a couple of months and flowers attract hummingbirds and small insects. Seeds are tiny and are eaten and moved about by ants and other small creatures. In shady garden beds, Heuchras combine nicely with sword ferns (Polystichum munitum), shade-loving bunchgrasses (Deschampsia spp. and Melicas), Columbine (Aquilegia formosa), and succulent Dudleya species. Pink-Flowering Currant (Ribes sanguineum) and Mock-Orange (Phildaelphus lewisii) are shrubs that like the same conditions and can create the ‘bones’ for a gorgeous display in June!
I am particularly fond of ‘Old la Rochette’ with nice light pink flowers – and ‘Opal with white flowers that gradually fade to pale pink. ‘Lillian’s Pink has bright pink flowers.
Another member of the family ‘Fringecups’ (Tellima grandiflora) looks very similar in leaf to Heuchra but the flowers are tiny, (hardly grand!) with fringed petals and very sweet upon a closer look. The leaves are also very similar but with a veined pattern on both the top – and more so – on the underside of the leaf. These are much tougher plants which do fine with more sun – and for the most part, are ignored by the deer.
‘Coral Bells’ (H. sanguinea) are native to Arizona and New Mexico and are quite commonly available in the average retail nursery and often sport red flowers. Also common and available are Heuchras with a variety of leaf colors – these plants have been developed by hybridizing the California native species with the southwestern species.