These are woodland plants from North America and Asia, related to Heuchera, with which hybrids called x Heucherella are easily produced. They are known in America as foamflower, which gives a clue to their appearance. They make upright spikes packed with masses of small, starry flowers, usually white or pale pink. There are now a lot of Tiarellas and relatives with interesting foliage colour, providing long-lasting focal points in shade places.