How-to Guide
How to Grow Crocus
The short answer
Crocus are fall-planted, spring-blooming corms. Clemson Extension recommends planting them in November, 3 inches deep and 3 to 4 inches apart, in full sun or light shade with well-drained soil. As with other spring bulbs, wait until the soil temperature at planting depth stays below 60 F before planting.
After they flower, leave the leaves on the plant for at least six weeks or until they turn brown — that foliage feeds next year's bloom. Clumps that get crowded and bloom less can be separated every few years.
What a crocus is
A crocus grows from a corm rather than a true bulb — a compressed stem that stores food with a bud on top. Like other hardy spring-flowering bulbs, crocus need a cold period in the ground: Clemson notes most spring bulbs require a 12- to 16-week chilling period to produce flowers, which is why they are planted in fall and bloom in early spring.
When and how deep to plant
- 1Time it by soil temperature — Plant in fall — Clemson suggests November in its region — once the soil temperature at planting depth stays below 60 F.
- 2Plant 3 inches deep — Set corms 3 inches deep and 3 to 4 inches apart, pointed side up. The general Clemson rule for spring bulbs is three to four times as deep as the bulb is wide, measured from the base.
- 3Plant in drifts — Crocus read best in clusters rather than single rows; their small flowers get lost when planted one by one.
Sun, soil, and water
Give crocus full sun or light shade and well-drained soil — poor drainage rots bulbs and corms of all kinds. Fall and winter moisture usually suffices; no fertilizer is necessary if you only want one flowering season, per Clemson.
After-bloom care and dividing
Do not cut or mow the grassy foliage after flowering. Leave it at least six weeks or until it browns so the corm can store energy. If a patch becomes overcrowded and flowering drops off, dig and separate the clumps every few years once the foliage has died down, then replant at the same depth.
→ Crocus is flagged in our safety review. If you have pets that dig or chew, verify the specific plant against the ASPCA toxic-plant database or your local Extension before planting — and be aware that plants sold as 'autumn crocus' can be a different genus entirely.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- Clemson Cooperative Extension HGIC — Spring-Flowering Bulbs — Crocus planted in November, 3 inches deep, 3-4 inches apart, full sun/light shade; soil below 60 F before planting; 12-16 week chilling; leave foliage six weeks after bloom; separate overcrowded clumps every few years