Acorus gramineus ‘ Aureo variegatus’ Sweet Flag
South-east Asia is the home of this small species, or rather form, often found in reference books under the name Acorus pusillus or A. gramineuspusillus. It grows in the mountains at elevations of about 1,000 m (3,300 ft) on stones in mountain streams as well as on rocks sprayed by waterfalls, but definitely not in mud as is generally stated, though it can, in fact, be grown in mud.
Two cultivars are generally encountered in cultivation — the one shown in the ** illustration with green and yellow striped foliage and ‘Argenteostriatus’ which is longitudinally striped white instead of yellow. The plants are 20 to 40 cm (8 to 16 in) high. The leaves, growing from a short rhizome, are not divided into a stalk and blade but are sword-shaped.
Theare not particularly striking — the spadix is yellow green and grows up and outward from the stem, the spathe is green, reminiscent of a leaf, and likewise grows upward. The fruit is a red, many-seeded berry. As a rule, neither flowers nor fruits are produced in cultivation.
The entire genus contains only two species, the one described and Acorus calamus, the common sweet flag found growing on the margins of European ponds. It, too, is native to tropical Asia but has become naturalized in Europe, where it was first introduced by Clusius in 1574 — at the Vienna botanical gardens.
These small plants should be grown in a paludarium located in a conservatory, porch or glassed-in terrace, for they appreciate cooler conditions in winter. They may also be grown outdoors by a pool but then they should be covered with a thick layer of leaves and evergreen twigs in winter to protect them from frost. If the paludarium is located in a warm room and fitted with fluorescent light then this species may also pass the winter in warm condi-tions.
Propagation is by division of the clumps, and the plants should be grown in a mixture of loam and peat.