Trillium bulbs refer to the underground storage organs of trillium plants, specifically their rhizomes or tubers. Trillium is a genus of perennial flowering plants native to North America and Asia. These plants are known for their distinctive, three-petaled flowers and often grow in woodland habitats. Trillium bulbs are planted in the soil and give rise to new plants. They are typically dormant during the winter months and sprout new growth in the spring. Trillium bulbs are sometimes sought after by gardeners and collectors for their ornamental value.