Guide to growing Obedient Plant - Physotegia

Plants belonging to the hardy perennial genus Physotegia are stiff and range in height from 30cm to 1.2M.

They bloom from the middle of summer until early autumn.

Physotegia carry spiky tubular shaped flowers that may be pink, purple or white.

Some common names for Physotegia include Obedient Plant and False Dragonhead.

How to grow Obedient Plant

Obedient Plants can be grown outdoors from seed; sow them, and lightly cover with soil at the start of spring or autumn. It is best to sow small species about 30 to 50cm apart and space larger Physotegia varieties at about 60cm. The soil that obedient plants grow in should be cool, light and slightly acidic (pH 5 to7). Physotegia species can be grown in sunny or partially sunny parts of the garden. If growing in sunny areas ensure that the soil is kept moist.

When growing in the greenhouse first it should take Obedient plants from two to four weeks to germinate at 15 to 25 degrees centigrade. They should be started about two months in advance and transplanted into the garden just before the last frost of spring.

Caring for Obedient Plants

Obedient plants and Physotegia are easy to look after, but unlike their name suggests they are not obedient. They are liable to spread so cut the roots back hard to stop them from spreading. The soil that they grow in should be kept moist in dry periods by watering. It is also necessary to supply mulch to the plants to ensure that the soil stays cool. At the end of the season cut the plant back to the ground (autumn).