Trillium angustipetalum, commonly known as narrowpetal wakerobin, is a rhizomatous perennial herb that is native to the understory of mixed-evergreen and redwood forests, as well as the moist, shaded conditions of coastal woodlands in northern and central California, extending into southwestern Oregon. It typically grows up to 28 inches tall and is notable for its trio of large green leaves, which are often mottled with darker spots. From March to May, it produces a single, nodding flower with narrow purple or maroon petals that are somewhat malodorous. The flower’s unusual appearance and scent are designed to attract pollinating insects.

Narrowpetal wakerobin is valued for its striking foliage and unique flowers, which can add an exotic touch to shade gardens and woodland plantings. It is best cultivated in cool, moist, well-drained soils rich in organic matter, and it prefers partial to full shade. This plant is relatively low-maintenance once established but may take several years to flower when grown from seed. It is not commonly used in urban settings due to its specific habitat requirements and slow growth rate. Gardeners should be aware that Trillium species can be susceptible to slug and snail damage, and over-collection in the wild has led to conservation concerns.CC BY-SA 4.0