Crocus - An Early Start To Spring

Crocus (Crocus spp.) can be your wake-up call that winter is coming to an end (USDA hardiness zones 3- 8). They bloom in late winter (in the south); fall blooming varieties are also available. Bulbs (they're actually "corms") are available in flower colors from blue, purple, white, yellow, and mixed shades.

Choose from large and small flowered types. Six petal, cup shaped flowers stand tall above the foliage which emerges as bright green blades of grass with a center white stripe. The grassy foliage grows taller after flowers wither away.

Crocus thrive in full sun and tend to bloom earlier than those planted in partial shade. They prefer a well-drained soil with pH of 6.0 - 7.0. Crocus generally fail when sown in soggy ground.

Flower buds open to warming early morning sunlight, and close up in cloudy weather and in the evening. Crocus bloom and easily naturalize where winters are cold. Sow corms in mid-fall because they require 12-15 weeks planted in cold soil (35 - 45 °F) to initiate their blooms.

Crocus grow 3- 8 inches high depending on variety. Sow drifts of crocus in several places around the garden, under trees, sprinkled in the lawn, in alpine and rock gardens, and in containers. Interplant crocus with short growing narcissus, hyacinths and tulips, and pansies and violas. Plant them where perennials emerge in mid-spring and crocus foliage has died back.

Crocus thrive in the garden for many years. Eventually, some in the planting may decline due to virus diseases which distort the leaves and cause streaking; bloom buds may fail to open. Dig up and dispose of virus infected plants to prevent spreading diseases. Crocus are generally critter-proof, but areas overpopulated by deer, chipmunks, rabbits and squirrels may dig up corms or chew down leaves and flowers. Voles also feed on corms.

The ancient Greeks collected and dried the stigmas from autumn-flowering crocus (C. sativus) to make saffron herb used in food dishes.

Crocus may be purchased at most garden centers in the fall. For a wider choice in varieties, buy from a mail order supplier like Brent and Becky's Bulbs in Gloucester, VA. They also sell fall blooming crocus.

Winter Flowering Bulbs

Photo: Galanthus naturalized in woodlands (courtesy of Brent and Becky's Bulbs)

These bulbs are the early birds. Give them a week of warm weather in the 50's, nights slightly above freezing, and little to no snow cover. A beautiful flowering patch of winter aconite (Eranthis), snowdrops (Galanthus), glory of the snow (Chionodoxa), or early crocus appears in January and February in USDA zone 6 and 7.

These "special" bulbs naturalize and come back every year. Bulbs are planted in the fall and are purchased from bulb emporiums on-line or through mail order nursery catalogues. Two personal favorites for purchasing bulbs are Brent and Becky's Bulbs in Gloucester, VA and van Bourgondien's Bulbs in Dix Hills, NY.

Dec. 21, 2009 conversation with Brent Heath: he identified additional early flowering gems in the winter garden in zone 6: The earliest daffodil is Narcissus 'Rijnveld's Early Sensation' with golden yellow opening in mid-to late January in zone 7. Flowers last and last in the cold winter weather. Many species crocus bloom in February and March. Crocus ancyrensis 'Golden Bunch' opens with small tangerine yellow blossoms, one of the earliest to bloom in the winter season. Other early bird crocus species are C. imperati and C. tommasinianus.

Muscari armeniacum 'Christmas Pearl' bears 4-6 inch double blue flowers beginning in late February.