Care of Crocosmia

Crocosmia , a member of the iris family, is fairly easy to grow. They originated in South Africa, and grow well both in the ground and in containers. They should be planted in spring and divided, if needed, in the fall. Care is similar to other flowering bulbs.

Sun and Temperature

• Crocosmia like full sun and don’t shy away from direct sunlight. They are tougher than some other flowering bulbs and can withstand some cold temperatures, up to zones 5 or 6 on the U.S. Department of Agriculture’s cold hardiness zone map (See Resources). Crocosmia will not survive temperatures colder than about 15 degrees below zero, however, even with generous mulching in winter. Gardeners in colder climates should dig up the bulbs and bring them indoors for spring replanting.

Water and Soil

• The plants should have rich soil, although you don’t need to fertilize it unless the soil is poor. Crocosmia like loose soil as well, so loosen up any tightly-packed clumps before planting the bulbs. If the soil is too clay-like or heavy, mix in some sand or loose mulch to help it drain better. Water only when the soil is dry; they prefer soil to be moist, not wet. If planting in containers, be sure the pot has drainage holes and water carefully as the crocosmia won’t survive in very wet soils.

Other Considerations

• Use pesticides and fungicides if needed, but crocosmia is not prone to pests or diseases. They are a perennial, so when they die back in the fall, cover them with mulch to protect from freezing, and they grow back in the spring. Dig up and divide crocosmia every three or four years to keep them blooming heartily.