This rhizomatous plant grows 20 to 45 cm tall. Its leaves and the different parts of its flower are grouped in threes. Its large, solitary flower is bright white. It turns pinkish with age. Its fruit is a berry, red at first and becoming blue-black as it ripens.
This plant grows 20 to 45 cm tall. It has a more upright bearing than other trilliums (its stem is erect). As its name indicates, several of its parts are grouped in threes, including its large, broadly ovate leaves and its solitary flower with 3 dark red petals.