12-18" tall x 9-12" wide. Trillium cuneatum (Sweet Betsy Trillium, also known as Toadshade) is an easy-to-grow trillium that spreads via underground rhizomes. Plants do not take well to being moved once they’re established in the garden. They thrive in partial to full shade in rich, slightly moist, slightly acidic soils. When left alone they will form large colonies. Like many spring wildflowers, Toadshade Trillium will enter a dormant period during the mid to late summer during which the foliage will die back. If you must transplant or divide the colony, this is the time to do it. For best growth, mulch yearly with chopped leaves.