Japanese name: ジャスティシア ベトニカ Scientific name:Justicia betonica
[Overview]
A subshrub up to 1.5 m tall.
The leaves are simple and opposite, elliptic to ovate, up to 22 cm long and 12 cm wide.
The leaf margins are entire.
A square columnar spike 10–20 cm long is produced at the stem tip.
Ovate to heart-shaped bracts overlap on the inflorescence, white with green veins.
The flowers are 1.5 cm long, pale reddish purple and two-lipped; they protrude from the bracts but soon turn brown.
[Uses]
In Africa it is used medicinally and as a milk-promoting agent for dairy cows.
[Cultivation]
Propagate by cuttings.
It can overwinter if the temperature stays at 6–8°C or above.
It prefers sun to partial shade and fertile, well-drained soil.
With poor sunlight it becomes leggy and flowers poorly, but direct summer sun can scorch the leaves.
For potted plants, from spring to autumn water thoroughly when the soil surface dries, and keep it on the dry side in winter.
For plants in the ground, watering is unnecessary unless sunny weather continues and the soil becomes dry.
Less fertilizer keeps the plant compact, so apply liquid fertilizer about once every 2 weeks from spring to autumn.
Pests and diseases include scale insects and spider mites.
