Crocosmia grow from corms at the base of the plants and are naturally clump forming, multiplying regularly – some varieties more so than others. The best time to divide and replant congested clumps is in Spring. They prefer to be in full sun or partial shade in moderately fertile well-drained soil. Cover the crown of the plant in Winter with mulch or bark chippings to protect against frost.
As a rough guide when planting Crocosmia as ground cover – 4 plants per square metre is adequate with a little patience, 6 will give better coverage, and 9-12 will make a weed supressing carpet very quickly.
How to grow Crocosmia
Position: Sun/partial shade
Foliage: Perennial, leaves appear from early Summer with flowers following mid-late Summer to mid-late Autumn
Soil and site: Moderately fertile, well drained
Flowering time: Mid-late Summer
Growth rate: Moderate
Ultimate height and spread: Between 60cm and 150cm depending on variety, with an average spread up to 60cm
Hardiness: Fully hardy
Aftercare: Water well until established, avoiding soil becoming waterlogged. Cover the crown of the plant in Winter with mulch or bark chippings to protect against frost. Divide and replant congested clumps is in Spring.