Sunday, March 1, 2009
Farrar in his book ‘The English Rock Garden’ describes this plant as “one of the most noble and beautiful plants in the world”. Flowering in April its formal upright elegant shape is an impressive sight just as winter approaches.
Colchicums are often called ‘Autumn Crocus” but they are no relation to true crocus which belongs to the family Iridaceae (Iris Family) and Colchicum belongs to the Lily Family (Liliaceae). The quick reference to identify the difference is to count the number of stamens. Crocus has three and Colchicum has six.
The name Colchicum is derived from Colchis the ancient name for the Black Sea Region which includes Caucausus, Northern Turkey, Iran and Asia Minor. The various species can be found growing from sea level to 2000 metres on the Mountain slopes.
C. speciosum produces the largest flowers of all Colchicums. These giant tulip like cups are carried noblely on strong, elegant stems up to 300mm high. Within this species flower colour varies between deep crimson and rich lilac but in all cases they have a white base. They remain upright longer than other species. All colchicum are nudifloral plants which means they flower before leaves appear.
After flowering in April/May strong wide leaves appear and grow right through until January when they die off. In summer the bulbs like to be hot and dry which aids future growth and flowering.
The corms are larger strong irregularly shaped and covered by a strong dark brown tunic. They divide readily and like to naturalise in good soil. If they get too crowded the quality of the flowers deteriorates. They should be dug and divided at this stage. Colchicums prefer good drainage and like to experience cold winters and hot summers.
These are several varieties and hybrids of C.speciosum. C. speciosum “Album” is a large pure white goblet with a green stem. It is an exceptionally beautiful flower especially in the gloom of autumn. “The Giant” is hybrid which has large lilac flowers and a white stem.
An excellent account of Colchicum can be found in EA Bowles 1952 book ‘A Handbook of Crocus and Colchicum for Gardeners’ for those interested in obtaining more information.