Plant of the Month for February, 2012

(try-SIR-tiss HUR-tuh)

General Information:

Commonly called toad lilies, Tricyrtis will be the last flowering plant in your fall shade garden, providing much needed colour at that time of year. The cultivar  ‘White Tower’ is one of the earliest blooming Tricyrtis, forming strong upright-arching stems that start blooming in mid fall and continues blooming until frost.  The flowers are about 2.5 cm (1 in) across and look like small orchids.

The name Tricyrtis comes from the Greek "tri" (three) and "kyrtos" (swelling, arched, bulging or humped) which refers to the 3 sack-like nectaries at the base of the tepals. The flowers tend to have bumps on them which probably accounts for the ‘toad’ in the common name. Although they are usually considered to be part of the Lily family, they are not bothered by the lily beetle. 

            

Tricyrtis hirta 'White Tower'; photo by Robert Pavlis

Toad lilies form clumps that are slow spreading. The 4-6" long leaves are arranged alternately on the stem and are lanceolate to ovate in shape. All parts of the plant are covered with very fine, transparent hairs. Rabbits will nibble on new growth in early spring but don’t bother the plant once it starts growing. Deer leave Tricyrtis alone.

      

Tricyrtis hirta 'White Tower'; photo by Robert Pavlis

In recent years a Tricyrtis virus has been identified that is spread by aphids. This virus causes the flowers to become mottled and may turn them completely purple. This virus does not seem to weaken the plants and most growers and nurseries don’t seem concerned about it. In fact several cultivars with mottled flowers have been named and are routinely sold. These include 'Raspberry Mousse' and ‘Empress’. There is no evidence that the virus affects other types of plants.

            

Tricyrtis 'Empress'; photo by Robert Pavlis

          Life Cycle: perennial

Height: 20 cm (8in)

Bloom Time: mid to late fall

Natural Range: East Asia in areas corresponding to roughly zone 5 and warmer

Habitat: Wide range of habitats, at the edge of forests along river banks and on sloped ground

Synonyms: none

 

Cultivation:

Light: part shade to full shade, bloom better with more light                               

Soil: normal well draining with some humus, prefers slightly acid soils but grows well in slightly alkaline soils

Water: moderately moist to wet                         

 USDA Hardiness Zone:  4 to 8 for Tricyrtis hirta

Propagation: division in spring once new buds start to grow, cuttings in summer before flowers open, and grown easily from seed. Tricyrtis  ‘White Tower’ comes true from seed.

Seedex availability (ORG&HPS annual Seed Exchange): available most years

Robert Pavlis