Plant the bulbs in masses 3 inches deep and 6 inches apart. Colchicums are hardy to USDA Hardiness Zone 5. An interesting fact concerning colchicums is that the dried corms and seeds of Colchicum autumnale are the source of medicinal colchicum and colchicine. Colchicine is used in plant breeding work to induce mutations. Showy crocus is a fall-blooming crocus.
Flowers are violet blue with yellow anthers and deep orange stigmas.
Plant height is approximately 5 to 6 inches. Excellent varieties include 'Cassiope' which produces aster blue flowers with yellow bases and 'Conqueror' with clear, deep blue flowers. Showy crocus is easy to grow. Choose a well-drained site in partial shade to full sun. The bulbs should be planted 3 to 4 inches deep and 4 to 6 inches apart.