Tiarella wherryi 'Silverado'

Tiarella or foamflowers are native to the woodlands of North America and eastern Asia. It is a small plant with heart-shaped leaves that is attractive all year-round. It is an excellent groundcover, which makes a dense patch of foliage. In spring the plants give rise to spikes of starry white flowers on 25 to 30cm (10 to 12in) spikes give a 'foamy' appearance to the plants. They are breathtaking when viewed en masse as a sea of white foam.

Tiarella have strikingly similar foliage to Heuchera. You've probably seen the resulting cross between the two plants: 'Heucherella'. But unlike Heuchera, Tiarella are usually grown for their flowers which will bloom earlier than Heuchera. Tiarella plants once again provide the spiky bottlebrush foliage of both the Astilbe and Cimicifuga, which give the height and depth to the garden.
An easy plant to grow: low maintenance, good in shade, and a long bloomer. It also works well in pots and containers and is very useful for shaded areas.

Native to America, Tiarella, often called foam-flowers because of their white blooms, have recently enjoyed a resurgence in popularity since they have been featured in the planting of the High-Line in New York. They can be found between the old railway lines, planted en masse to form an attractive ground cover

• Awarded the RHS Award of Garden Merit
  Tiarella wherryi has been awarded the Royal Horticultural Society’s Award of Garden Merit (AGM).

Sowing: Sow in Spring or Autumn
Tiarella wherryi; does not divide easily so is best increased by sowing seed.
Sow seeds in a tray of seed compost at 10°C (50°F) and place in cold frame to germinate. Germination is irregular 14 to 90 days. Prick out seedlings into trays of potting compost when large enough to handle, and grow on in a cold frame or nursery bed, until planting out in the following spring.

Planting:
Place the plants 15cm (6in) apart in well-drained, moist soil. Add a light application of organic fertiliser to the planting hole. Set the plants no deeper than they were in the container. Mulch around but not on top of the plants with 7cm (3in) of organic compost. Water well until the soil is completely moist.

Cultivation:
Tiarella prefers moist, humus rich, well-drained soils but will not tolerate waterlogged soils.
Cut back old flower stems with scissors to neaten the plant. Apply a light application of organic fertiliser to the top of the soil in spring. Water weekly until the soil is completely moist in dry summers.
If you need to divide the plants, do so in early spring.

Plant uses:
Ground-cover, shade garden, beneath trees, rock gardens or borders, natural woodland gardens.
Plant en masse for best effect.

Origin:
Tiarella are native to the woodlands of North America and eastern Asia. It can be found in Nova Scotia and the Appalachian Mountains to Alabama West to Minnesota.
It is a member of the saxifrage family, Saxifragaceae.

Nomenclature:
The genus name Tiarella is taken from the Greek word tiara, meaning a turban or small crown, referring to the shape of the fruit.
The species name wherryi is named after Dr. Edgar T. Wherry (1885-1982) an American mineralogist and botanist who discovered this species.
Tiarella wherryi is synonymous with Tiarella cordifolia. In Latin, cordifolia means ‘with heart-shaped leaves’, although maple-leaf-shaped might be more accurate.
It has the common names of Mitrewort and Foamflower, or Foam Flower owing to the frothy appearance of its clusters of star-like white blooms.

A “New Plant”:
Until relatively recently the foamflowers have been grown almost entirely in woodland gardens devoted to native plants. The richness of variation in the group and the attractiveness of many forms have given them success as mainstream garden perennials for use in shaded sites.
In the late 1980s the hybrid crosses were made by Charles Oliver at The Primrose Path in the US that have provided the basic material for the almost all of the new cultivars that have come onto the market in the 1990s.

Heuchera, Tiarella and Heucherella: A Gardener's Guide” by Charles Oliver.
Charles Oliver describes the varieties that gardeners are likely to find for sale at nurseries and give a list of the cultivars that will perform best. The full range of heucheras is covered, from ones for the perennial border to those for naturalising or growing in troughs with alpines, and also describes and critique heucherellas and tiarellas. The related mitellas and tellima are included, too.
Other chapters are on the history of breeding work with these plants and on how the traits of the wild species came to be combined as they are in the modern hybrids. There are also many colour photos.