It is a shrub, growing to 2.5 m (8.2 ft) tall and broad, that produces masses of flowers in a range of colours from light-pink to orange to bright red.
The species name "mammosa" means "with breasts" and refers to the udder-like tubular shape of the flowers.
This plant is increasingly popular as an ornamental garden subject. In the UK it has gained the Royal Horticultural Society’s Award of Garden Merit. Like many heathers it is a calcifuge, meaning that it must be grown in an acidic soil. It requires a sunny, sheltered spot with sharp drainage. It tolerates low temperatures down to 0 °C (32 °F), but will not stand freezing.