Crocosmia and Dierama
Divide Crocosmia and Dierama in spring
To remove the corms without damage, dig down 30cm (1ft) to avoid and gently lift
The roots of both perennials form ‘chains’ of corms, which can be replanted intact or individually separated. There is evidence that maintaining the ‘chains’ intact may be the better option
Discard wizened or diseased corms and trim old leaves
Replant sections at their original depth
Some crocosmias, such as Crocosmia ‘Lucifer’ and C. × crocosmiiflora ‘Jackanapes’, produce underground stems (stolons) which can be detached, along with fibrous roots, to produce new plants. However, it is worth noting that crocosmias flower profusely when crowded, so do not divide clumps too often – every two or three years should be enough.