Propagation
Take soft tip or semi hardwood cuttings with a heel from autumn to winter and cut them up to 40 mm (1? in) long.
Sow fresh seed during spring.
Culture
Prune regularly to maintain a compact shape and encourage flowering using hedge clippers. Cutting back old woody plants hard may cause dieback. It is also susceptible to caterpillars.
Botanic information
Leaf: The linear leaves have recurved-dentate margins and are aromatic when crushed. Both sides the leaves are covered in a fine soft grey pubescent.
Flower: A colourful leafy bract conceals the tiny 2-lipped blue tubular flowers that are arranged in a dense terminal spike-like raceme that is up to 150mm (6in) long and appears during spring.
Fruit: The fruit is 4-small nutlets that are hidden amongst the bracts and not commonly seen. Flower heads are normally removed during cultivation and the small seeds are viable but the plant is commonly reproduced vegetatively.