Plant Common Name
Giant Autumn Crocus
Prized for its rosy-purple flowers that appear in late summer and early fall rather than in spring like those of most other "bulbs," this hardy perennial is native to northern Turkey. It has been known in gardens since the late nineteenth century. Although sometimes called "autumn crocus," it is not related to the genus Crocus, which is in the iris family.
This plant produces large broad strap-shaped leaves in spring, which gather energy for the underground bulb-like storage organ, known as a corm. In late summer, some 3 months after the leaves have withered, one to three funnel-shaped flowers arise on white, ankle-high, stalk-like floral tubes. Appearing about midway through the colchicum season, the blooms have six oval petal-like segments. They open wide in bright sun to display the orange-yellow anthers and a white eye. The large broadly conical corms may double or even triple in number each year, eventually forming a large clump that provides a spectacular fall show.
Colchicums do best in full to partial sun and deep, moist, fertile, well-drained soil. The corms are often planted under low groundcovers like creeping juniper or ivy, which provide a green background and support the blossoms during wind and rainfall. This lovely perennial also is perfect for bringing new life to the late-season perennial garden or shrub planting. It works well in meadows and flowering lawns. The corm will bloom even if not in soil! Purchase the corms in mid- to late summer, so they can be planted before they bloom.
All parts of Colchicum contain the potent alkaloid colchicine; see http://www.ces.ncsu.edu/depts/hort/consumer/poison/Colchau.htm
AHS Heat Zone
9 - 1
USDA Hardiness Zone
5 - 9
2a, 2b, 3a, 3b, 4, 5, 6, 7, 8, 9, 10, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
Bulb or Corm or Tuber
Full Sun, Partial Sun
4"-6" / 10.2cm - 15.2cm
5"-10" / 12.7cm - 25.4cm
Early Spring, Late Summer, Early Fall, Fall, Late Fall, Winter, Late Winter
Europe, Turkey, Central Asia, Western Asia
Spring, Fall, Winter
Alpine, Container, Cutflower, Foundation, Lawns and Turf, Mixed Border, Rock Garden / Wall, Wildflower
Sharp or Has Thorns