Propagation
Sow fresh seeds during autumn and place in a cold frame to germinate.  Germination may take up to two years and seedlings reach flowering size in five to seven years.  

Division of the rhizome with at least one growing point after flowering. The plants are slow to re-establish.

Botanic information
Leaf: The sessile broad-ovate to rhomboid leaves have an acuminate apex. The upper surface is a dark green commonly marbled in maroon or greyish-cream and the underside is pale green. The leaves are arranged in a whorl of three at the apex of the stems.

Flower: The sessile funnelform flowers have 3-green lanceolate sepals and 3-spreading petals that are white, yellow-green or purplish brown. The centre consists of 6-flattened yellow stamens and the terminal flowers appear solitary during spring and are accompanied with leafy bracts.

Fruit: The 3-celled berry contains winged seeds that are viable but the plant is commonly reproduced vegetatively to maintain true to type.

Trillium culture
Plant rhizomes from autumn to spring at a depth of 80 to 100 mm (4in) deep in groups and space 300 mm (1ft) apart. They tolerate most well drained cool moist soils with ample humus and with the addition of rotted cow manure incorporated into the soil. 

During summer keep the soil continuously moist, particularly during hot weather and grow the plants in a semi-shaded, wind protected position.