Western trillium is a distinct, stunning wildflower celebrated across the Pacific Northwest, including at Tryon Creek's Trillium Festival. Bulbs announce spring each year with a triplet of leaves topped by bright white flowers that illuminate the woodland garden in April, then fade from pinks, to purples and eventually brown before withdrawing completely back to the bulb to wait for next year. This is a slow growing but exceptionally long-lived plant, stemming from rhizomes and creating a larger clump with more abundant blooms over many years.
- Plant type/canopy layer: deciduous perennial herbaceous plant
- Size at maturity: 4-18", 6-24" wide
- Light requirements: full shade, part-sun/part-shade
- Moisture requirements: moist soil, well-drained
- Bloom time: March - July
- Growth rate/ease: grows slowly, moderately difficult to grow
- Wildlife support: attracts and supports bees, particularly the bumble bees that pollinate it, and other insect pollinators, beneficial and pest eating insects
- Native habitat/range: grows in mixed forests across most of the Pacific Northwest from the Cascades to the coast. Portland Plant List - yes.
- Special features & uses: medicinal; landscape uses include woodland gardens, shady pollinator gardens and shady raingardens
Gardening with Western Trillium: Trillium is one plant where the right conditions truly matter. You'll enjoy watching it thrive in moist, acidic soils that contain lots of organic matter, such as a mature forest garden where leaf litter and woody materials are left in place. Like many bulbs, be sure the soil is moist but well draining, so the bulb doesn’t rot. Trilliums can withstand minor summer drought, but supplemental water in the summer is necessary for the first few years after it’s transplanted. Admire its blooms in nature, not in a vase - as picking them will significantly diminish the plant, often eliminating blooms for several years! It is also adored by slugs. Like many native plants in the Lily Family, the berry-like fruits evolved to have a fleshy appendage called elaiosomes that are both attractive and nutritious for ants. These tiny workers haul the seed back to their underground nests to feed the elaiosomes to their young, and leave the remaining seed embedded in their underground nests. In doing so, they are critical players in a magical dance of seed dispersal that mutually benefits both the plants and the ants. So, think twice next time you reach for that outdoor ant killer.
Photo Credit 1: Tara Lemezis, Tiny Seed Photography
Photo Credits 2 - 4: Tracy Cozine & Nikkie West, Sparrowhawk Native Plants