May 5, 2007 4 min read

While walking through the local woods at this time of year, if you ever came upon a large patch of the hazy flowers of Tiarella cordifolia, you would know instantly why this low-growing native plant has the common name “Foamflower.” From a distance, a carpet of these flowers looks as if someone poured a capful of liquid soap into a fountain and the resulting foam spilled over and across the woodland floor.

But don’t be deceived by the delicate looks of these flowers. Tiarella is a hardy, semi-evergreen woodland species that hybridizers have been working with for many years, and more and more gardeners are recognizing its value in the cultivated shade garden.

Interestingly, some of the hybridizing work is going on in our Southwestern Pennsylvania backyard. Charles and Martha Oliver have been selectively hybridizing tiarella for some 20 years here in Fayette County, and they have introduced several excellent cultivars into the marketplace. ‘Pink Brushes,’ for example, was selected for its excellent flower color. The cultivar ‘Elizabeth Oliver’ was selected for its burgundy-marked leaves and light pink flowers, and is one of the most widely-sold tiarellas in the country. So good is this cultivar, ‘Elizabeth Oliver’ has served as a parent of many new varieties of foamflower.

The Olivers are not alone in the tiarella hybridizing arena. Terra Nova Nursery has introduced a few, too, including ‘Jeepers Creepers’ and ‘Neon Lights,’ both boasting large leaves with dark purple patterning. And there are other hybridizers. (Neither the Olivers or Terra Nova sell directly to gardeners. Check mail order sources and garden centers for their named cultivars.)

I had the opportunity to talk with the Olivers recently, and it is apparent that they enjoy their “parenting” work. Variations in leaf shape, size and coloration, as well as the flowering quality, all figure in to final decision whether or not a hybrid is worth keeping or if it winds up on the compost heap.

There is a bit of discussion in the plant world, the Olivers told me, as to how many tiarella species there are in the United States.

Tiarella cordifolia is found in eastern North America, however, characteristics of the plant that grows up north is different than what grows in the southern Appalachians. Here in the north the eastern tiarella spreads by stolons, or runners, and it forms a ground cover. From about Virginia and southwards the plant grows as a clump-it does not have stolons. The leaves are a little different north and south, too. To help eliminate confusion, each of these Tiarella cordifolias have been given variety names: the northern variety is T. cordifolia var. cordifolia, and the southern one is T. cordifolia var. collina (also called T. wherri).

Western North America is home to a different native foamflower, Tiarella trifoliate var. trifoliata. But in several books another western tiarella called Tiarella unifoliata is also listed.

And yet another species of tiarella is found in Asia.

All argument about the names aside, foamflower is a good addition to the shade garden for many reasons.

Foamflower’s tiny white, star-shape flowers are borne on racemes that stand well above the leaves. The flower buds generally appear pink-a very enhanced pink in some hybrids-and fade to white as the flowers open.

The leaves are quite exciting, too. Some are more heart-shaped, while others are deeply lobed. Some are mostly green, others speckled with burgundy, and yet others mostly dark in color with green edges. The leaf patterns that could be created by hybridizing seems limitless.

I’m planting several hybrid foamflowers in my shade garden as an alternative to hostas. Like hostas they have showy leaf patterns I can enjoy all summer, but deer don’t seem to bother them (unlike the hostas).

As I mentioned, now is a good time to see foamflower in the wild. At Ohiopyle State Park, along the Great Gorge Trail, they are typically in bloom between the last weekend in April and the first weekend in May. Even if you miss the flowers the unique variation of the leaves are worth examining.

Note to readers: Part of the April 21 Nature’s Garden column about trough gardens was inadvertently left out. To read the column in its entirety, visit www.brimo-cox.com/NG72-Trough_Gardens.pdf.

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Susan Brimo-Cox gardens, observes nature and writes in Ohiopyle. Readers can send questions or comments to her at naturesgarden@brimo-cox.com.

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