Trillium grandiflorum, commonly known as great white trillium or wood lily, is a simple, graceful perennial that is one of the most familiar and beloved of the spring woodland wildflowers in eastern North America. It is native to rich woods and thickets from Quebec to Ontario to Minnesota south to Alabama and Georgia. Leaves, petals and sepals all come in groups of three. From an underground rhizome, a stout, unbranched, naked stem rises in spring to 8-18" tall topped by an apical whorl of three prominently-veined, ovate to egg-shaped, green leaves (each typically to 3-4" long but sometimes to 6"). From the center of the leaf whorl emerges a single flower in April-May on an erect to leaning stalk rising above the leaves to 2-3" tall (pedunculate). Each flower (to 3 1/2" across) has three flaring, ovate, wavy-edged, white petals subtended by three smaller green sepals. Flower petals are reflexed at the tips. Flowers acquire pink tones with age. Flowers give way to berry-like capsules. Seeds are disbursed by ants. Foliage will usually die to the ground by late summer, particularly if soils are allowed to dry. Additional common names for this trillium include large-flowered trillium and wake-robin.
Easily grown in deep, rich, humusy, moist but well-drained soils in part shade to full shade. Needs regular watering. Apply leaf mulch in fall. Rhizomatous plant that can be slow and difficult to propagate from seed. Spreads very gradually if left undisturbed. Garden Uses. Woodland gardens, wildflower gardens and moist shady borders. Hardy in zones 4-8.
Sowing: To break their dormancy, these seeds need to experience cold and warm moist periods followed by another period of cold moisture. Mix the seeds with a small amount of damp sand and place in a sealed plastic bag; store in a refrigerator for 30 days, then at 70-75 degrees F for 30 days, with a final period of 30 days in the refrigerator. Sow the seed 1/2" deep in a germination flat, keeping the soil lightly moist and at room temperature until germination. Alternatively, this seed can be direct sowed outdoors in late fall and allowed up to two years to germinate.
Growing: Water seedlings regularly until they become established; this plant develops rather slowly and may not produce blooms until its fourth or fifth year of growth. In order to thrive, it must have moist, rich soil. Excessive heat or drought may cause early dormancy. Mature plants may spread slowly by rhizomes. This plant makes an ideal choice for shade or woodland gardens.