Tiarellas and Other Relatives

Close relatives of heucheras, tiarellas, also known as foamflowers, are more delicate in every way.

Credit: Stuart McCall

Close relatives of heucheras, tiarellas, also known as foamflowers, are more delicate in every way.

A single plant might hold its own in a container, but for the garden it’s well worth buying at least three to make an impact. They are nominally evergreen, but named varieties tend to disappear over the winter, and some in my garden have never reappeared. Nevertheless, their charm keeps me going back for more. Most have lobed leaves with a long central finger and petite flower stems bristling with tiny pink and white flowers. Leaves generally start out plain green and develop their dark filigree of colour as they mature.

Among those with dramatic foliage, I’ve had limited success with ‘Mint Chocolate’, a contrast of bright green seamed with darkest purple, and better luck with ‘Inkblot’, whose young, slightly hairy, olive-green leaves grow brighter at the edges as they mature, while a black stain seeps out from the centre to cover the rest of the leaf. Winter adds a fine rim of rusty orange.

The species Tiarella cordifolia is native to eastern North America. Much more vigorous than its children, it will quickly cover a considerable area and is a useful groundcover in woodland gardens. In early spring, its fresh green foliage and froth of dainty white flowers make a pretty picture in the shade under evergreen shrubs.

Heucherellas, as their name suggests, are crosses between heucheras and tiarellas – x Heucherella – and have attributes of both species: the daintiness of tiarellas and the hearty constitution of heucheras. ‘Bridget Bloom’ has one of the most attractive flowers, tiny brushes of candyfloss-pink above green foliage. ‘Burnished Bronze’ also blooms pink, but its best feature is tan-coloured leaves with the smoothness and sheen of kidskin gloves. ‘Chocolate Lace’ offers the same illusion of fine leather in darker brown.

Tolmiea menziesii, a native of our region, is another close relative. A tough and enduring groundcover for shady areas, its distinctive characteristic is the way young leaves grow out of the centres of older ones, earning it the common names of “piggyback plant” and “youth-on-age.” Small, brownish-purple flowers have a quiet, woodland air. For more drama, there is ‘Taff’s Gold’, whose variegated foliage provides better contrast for the flowers. Like the tiarella clan, it’s a chameleon, leafing out a deceptively uniform green and assuming its bright marbling of yellow as it reaches full size.