Trillium rugelii aka Illscented Wakerobin

Trillium rugelii is a perennial from the southeastern United States. It belongs to the Melanthiaceae family and grows from rhizomes. Common names include southern nodding trillium and ill-scented wake-robin. It forms clumps, with upright stems and leaves that drop each year. Its low form suits planting beneath shrubs and other taller plants.

Plants reach about 1.5 feet (0.45 metres) in height. The listed garden size reaches 1.6 feet (0.5 metres) tall and wide. Each stem holds a whorl of three broad, oval leaves. These can measure about 0.7 feet (0.2 metres) long and wide. The leaves sit above the flowers, which hang beneath them. This gives the plant a leafy top above its nodding blooms.

The Chicago Botanic Garden lists flowering from May to June. Each flower has three cream-white petals and purple anthers. Pointed green sepals frame the petals. Each stem carries a single flower below its leaves. The pale blooms and broad leaves provide interest in shaded beds. Suggested settings include cottage gardens, informal borders, and planting beneath roses or shrubs. Its upright shape also suits the understory of a garden.

Grow this trillium in partial or full shade. Choose a sheltered site with deep soil rich in humus. Loam and sandy soil both suit it. Keep the soil moist, but allow excess water to drain. Acid to neutral soil is best. The RHS recommends adding leaf mould as mulch in autumn. North-, east-, and west-facing sites fit its listed growing conditions. Chicago lists USDA zones 6–7, while the RHS gives H4. That UK rating covers winter lows of about −10 to −5°C.

The RHS lists two to five years to reach mature size. Seed-grown plants take longer to produce their first flowers: five to seven years. Sow ripe seed in pots kept in a shaded cold frame. Another option is to divide the rhizomes once flowering ends. The plant needs no pruning. Slugs and snails may damage it, though the RHS reports few disease problems. These sources give no species-specific guidance on eating it or its toxicity. They also provide no details about its fruit.