Propagation
Sow fresh seeds during spring in boxes and prick out when large enough to handle.

Divide established clumps during spring.

Take soft tip cuttings of non-flowering shoots during early spring.

Botanic information
Leaf: The narrow mid-green lanceolate leaves have deeply veined upper surface and are arranged in opposite pairs. They are sessile and when crushed are slightly aromatic.

Flower: The small purplish tubulate flowers are arranged in a whorled spike-like terminal cyme that appears above the foliage on a tall scape during midsummer. The flower colour is occasionally yellow in the wild.

Fruit: The small nut contains viable seed that may self seed but the plant is normally reproduced vegetatively.