In colder regions, Crocosmia corms are lifted and stored when the foliage has died back to avoid frost. Store them in a cool and dry place free of frost till spring. In the milder areas, they are covered by a thick mulch cover over the tops in winter. Clean up plantation to eliminate leaves that have died. This is a seasonal treatment that guarantees that the corms survive and come back with green leafage and bright flowers the next year.