Colchicum bivonae

Colchicum bivonae is a corm-forming perennial in the Colchicaceae family. Its range spans southern Europe and reaches western Turkey. Records include Italy, Greece, Bulgaria, and the former Yugoslavia. It also grows on Sardinia, Sicily, and Corsica. In the wild, it inhabits mountain pinewoods and scrub. Records place these habitats around 1,640 feet [500 metres] above sea level.

This deciduous plant has an upright form and seasonal leaves. The RHS describes plants about 0.5 feet [0.15 metres] tall. Its broader garden size range reaches 1.6 feet [0.5 metres]. The listed spread also reaches 1.6 feet [0.5 metres]. Leaves emerge in winter and remain through spring. They are narrow and egg-shaped, and stand partly upright. The plant takes two to five years to reach maturity.

Flowers open in autumn and have a bowl-like shape. Their pink-purple tepals show a strong checked pattern. The centres often look pale or nearly white. Tepal tips may be sharp or rounded. The flowers also have a light scent. These blooms provide autumn interest in beds and borders. Suggested settings include cottage gardens, rock gardens, and gravel gardens. The RHS also recommends planting beneath roses and shrubs. PFAF lists sunny woodland edges as another suitable setting.

Grow this species in full sun and fertile, deep soil. Keep the soil moist, but ensure that water drains freely. Chalk, loam, and sand are all suitable soil types. It accepts acid, neutral, and alkaline conditions. Plant corms about 0.33 feet [0.1 metres] deep. Do this in summer or early autumn. The RHS gives it a UK hardiness rating of H5. PFAF lists USDA zones 5–9. It needs no pruning. Sow ripe seed in containers in an open frame. Another option is to detach small corms during summer dormancy.

Slugs may damage plants. Possible diseases include Botrytis grey mould, smuts, and tulip grey bulb rot. Every part is poisonous, with the underground corm posing particular danger. Eating it can cause severe gut injury and death. It is also toxic to pets. Handling corms may trigger skin allergies, so wear gloves. PFAF records no food or medicinal uses. It does report a plant-breeding use for extracted colchicine. This substance can double chromosome numbers to help produce new varieties.