Plant of the Month - March 2025
Colchicum bulbocodium.
GENERAL INFORMATION: Flowers that appear in the late winter (officially early spring), as the snow melts, are a joy to see. Most of our early bloomers are spring ephemerals which usually have white, yellow, blue or pink flowers. Some Crocus and Iris add purples and lavenders to the mix. One of my favourites is the hard to find, early flowering Spring Meadow Saffron, now Colchicum bulbocodium.
Unfortunately, the reference literature is often contradictory.
Synonym: Bulbocodium vernum, Colchicum vernum, (Merendera verna - misapplied).
Common Name: Spring Meadow Saffron.
Sub. Species: Colchicum bulbocodium subsp. bulbocodium, Colchicum bulbocodium var. edentatum, Colchicum bulbocodium ssp. versicolor.
Life Cycle: Perennial corm.
Height: 10 cm.
Bloom Time: Early April in Toronto.
Flower Colour & Size: 3-4 lavender-purple flowers appear with each set of leaves. 6 long tepals form a perianth tube, enclosing the ovary and reaching up from the corm. 6 bright yellow stamens are poisonous, as are all parts of these plants. 3 styles are united for almost all their length. (Separate in most Colchicum).
Leaves: Strap-like, glossy mid green leaves emerge just below and with the flowers, eventually forming a mound about 5 cm high to 15 cm wide. Ephemeral.
Fruit: Capsule, first developing underground, emerging after the leaves die down.
Range: Native in mountains from Southern Europe to North Caucasus.
Habitat: Alpine meadows.
CULTIVATION:
Plant: corms in the fall in groups 8 cm deep and about 10 cm apart.
Light: Full sun to partial shade.
Soil: Well drained, slightly acidic. Top dress with compost as the flowers fade.
Water: Dry to average.
USDA Hardiness: Zones 3-11.
Pest and Diseases: Usually disease and pest free.
Pollinators: Bees.
Companion planting: Other rock garden plants.
Propagation: After leaves die down, dig up and divide large clumps, then replant. Or grow from fresh seed. Stored seed might germinate using repeated cycles of 20°C, then 4°C, for 3 months each. Germination is very prolonged. Grow @ 4°C until a true leaf is well established.
Toxicity: Very poisonous, even to the touch. Edible saffron is a different family.
References:
Plants of the World Online https://powo.science.kew.org › taxon › urn:lsid:ipni.org...
https://www.missouribotanicalgarden.org/PlantFinder
https://onrockgarden.com/index.php/germination-guide
Https:pacificbulbsociety.org
https://plants.ces.ncsu.edu/plants/colchicum-bulbocodium
Text and images supplied by Anna Leggatt (Toronto Master Gardener)