Acorus

There are only two species in the genus Acorus, and only one of these, A. gramineus (grassy-leaved sweet flag), is often grown indoors. Its leaves, which grow in a dense clump or tuft rising from a slender rhizome that lies just below the surface of the potting mixture, are around J inch wide and up to 18 inches long. There is a green flower spathe, but it is barely noticeable since it is so fine that it looks almost like another leaf. A variegated leaved form, A.g. 'Variegatus,' has white stripes on its green leaves, as does the dwarf form A.g. 'Albovari-egatus,' whose leaves rarely grow much longer than 6 inches. All forms provide a pleasant contrast with the more substantial foliage of other house plants. Although acoruses grow more or less continuously, active growth will slow down under reduced light.

PROPER CARE

Light Medium light or direct sun­light filtered through a translucent blind or curtain will suit acoruses.

Temperature An indoor acorus will grow well in normally warm room temperatures but can also tolerate tem­peratures as low as 40°F. High hum­idity is essential; stand plants on trays or saucers of moist pebbles throughout the year, and mist-spray the leaves during warm periods.

Watering These plants must never be allowed to dry at the roots. Water plentifully as often as necessary to keep the potting mixture thoroughly moist. The pot may even be allowed to stand in a shallow saucer of water.

Feeding Apply standard liquid fer­tilizer every two weeks during spring and summer.

Potting and repotting Use a soil-based potting mixture. In spring move small plants into pots or shallow pans one size larger if their tufts of leaves have completely filled the surface area of the mixture. Five-inch pots or half-pots are likely to be the largest size needed. Propagation Propagate by separat­ing overcrowded clumps in spring or summer. Carefully pull clumps apart with the fingers, making sure that a piece of the rhizome is attached to each section, and treat each divided clump as a mature plant.