Japanese Rush – Acorus gramineus, commonly known as grass-leaf sweet flag, dwarf sedge, Japanese rush, and Japanese sweet flag, is a botanical species belonging to the genus Acorus, native to Japan, Korea in eastern Asia.
The Variegated Japanese Rush resembles the true aquatic Japanese Rush, but has long grass-like leaves that usually have 2 or 3 white stripes along each light green leaf. The leaves are tough and leathery and will grow to a maximum height of 35 cm.
Since it is not a true aquatic plant, the Variegated Japanese Rush does better in tropical aquariums where about half of each leaf is above water. It will grow in many substrates and the roots are thick and are quite capable of taking nutrients directly from the water. The Japanese Rush propagates by producing shoots from the base which will eventually spread and create their own plant.
Fertilising: Apply standard liquid fertiliser every two weeks during spring and summer.
Potting and repotting: Use a soil-based potting mixture. In spring move small plant into pots or shallow pans one size larger if their tufts of leaves have completely filled the surface area of the mixture. 13cm (5 inch) pots or half-pots are likely to be the largest size needed.
Gardening: Acorus gramineus when grow outdoor is easily grown in average, medium to wet soils in full sun to part shade. Grows well in both boggy conditions (including very shallow water) and consistently moist garden soils. Scorched leaf tips will occur if soils are allowed to dry out. Appreciates some relief from hot summer sun (e.g., afternoon shade or filtered sun) when grown in hot summer climates. Slowly naturalizes by spreading roots, but is not too aggressive.
Acorus gramineus can be planted in baskets in shallow water. It also makes a useful aquarium plant but is short-lived where water temperatures exceed 22°C (72°C) for long periods. Divide every few years to prevent congestion.
Propagation: Prapagate by separating overcrowded clumps in spring or summer. Carefully pull the clumps apart with the fingers, making sure that a piece of rhizome is attached to each section and treat each divided clump as a mature plant.