Trillium sessile aka Wood Lily

Trillium sessile is a woodland perennial in the Melanthiaceae family. Common names include toadshade, toad trillium, and wood lily. It comes from north-central and east-central parts of the United States. It grows in rich woods, limestone woods, and floodplains. In North Carolina, it has a small, local range. There it grows near the Roanoke River on rich lower slopes and natural levees.

Plants stand about 0.3–1 foot [0.1–0.3 metres] tall. They spread about 0.5–1 foot [0.15–0.3 metres] across. RHS gives a broader size range, reaching 1.6 feet [0.5 metres]. Thick underground rhizomes form clumps and spread slowly. Each stout, smooth stem stays unbranched and carries three leaf-like bracts. Stems range from green to reddish purple. The stalkless bracts form a whorl around the stem. They are oval to almost round, with smooth edges. Green, pale silver, purple, or bronze marks give them a mottled look. These marks fade as the bracts age.

Flowers appear in April and May, above the central leaf whorl. Each stem bears one flower without a flower stalk. Three narrow petals point upward rather than spreading flat. Their shades include maroon, dark red, brown-purple, and sometimes yellow-green. The strong scent can seem musky or unpleasant. It draws flies and beetles, which pollinate the flowers. Summer brings small red to burgundy fruits, under 0.08 foot [0.025 metres] across. These berry-like capsules have six parts. Ants carry the seeds, while small mammals eat the fruits.

Grow this plant in partial shade or full shade. It needs rich soil with humus and good drainage. Keep the soil moist and water it regularly. RHS favours acid to neutral soil and lists sand and loam. An autumn mulch of leaf mould suits its needs. It is hardy in USDA zones 4–8 and rated H5 in Britain. The leaves die back by midsummer, sooner when soil dries. Groups suit shaded woodland gardens and natural areas. Ferns and other spring wildflowers make suitable neighbours.

Established plants have few serious pest or disease problems. Slugs and snails may feed on them. Leaf spot, rust, and smut can occur. No pruning is needed, but moving plants can be difficult. Do not dig plants from the wild. Seed-grown plants can take five to seven years to flower. Sources record young leaves as edible, with NC State advising cooking. Yet NC State flags fruits and roots as possible low-severity poison hazards. The toxic compounds and symptoms remain uncertain. Recorded herbal uses do not establish medical safety or benefit.