Colchicum is a large genus in the Colchicaceae family found in Europe, North Africa and western to central Asia. They are all winter growers. There are both autumn and spring flowering species. Some of the autumn ones flower before their leaves appear. There is much confusion over the correct names of plants in the literature and misnaming in the trade as well so people will be growing plants under the wrong names. Many so-called species in cultivation are clones of hybrid or of uncertain origin. Many of the species do not have flowers and leaves at the same time which makes wild collection for herbarium specimens a challenge. We attempt on this page to be as accurate as we can be, but until there is a revision which name is correct will be a matter of opinion. Colchicum photos on this page and the hybrids page taken by Arnold Trachtenberg are grown in his New Jersey garden, planted in garden soil augmented with 50% grit.
Colchicum are notoriously difficult and slow to grow from seeds because the seeds will not sprout without summer heat treatment and a cool down period during the autumn. Diana Chapman provided the following valuable tips for successful germination. Seeds should be sown fresh in a well-drained mix, covered with one of two cm of grit or course sand. Keep the mix slightly moist during the warm days of the summer. It is best to leave the seeds outdoors where they can experience the summer heat and fluctuations in temperature. In the fall, water well and allow the seeds to germinate. Some species may take two years to germinate so keep your pots for at least 2 years. Sporadic germination had been observed by gardeners after many years. Some growers have good success with soaking the seeds 1-2 days before sowing. This can be done by simply soaking in a bowl of water or placing the seeds in a stocking, tie the end and placed into a toilet bowl (water reservoir). Every flushing will wash away the inhibitors and allows the seeds to germinate.
The paper "Effects of Stratification, Temperature and Light On Seed Germination of Colchicum Macrophyllum B. L. Burtt", by Anna Antonidaki-Giatromanolaki, Magdalena Dragassaki, Michael Papadimitriou, and Ioannis Vlah, Vol. 8, № 2, 2008: 105-107, Propagation of Ornamental Plants, concludes that the seeds need a warm moist period (eight weeks at 20C) followed by a move to cooler temperatures (10-15C) and darkness for germination.
The photos below show a few of the species.
For more photos and information about the species select the appropriate wiki page:
or click on the name in the table below: