Description - The flattened, silvery sheets of stems and leaves seen on the cliffs are very distinctive in this subspecies of Broom. The yellow pea-flowers are much the same as in Common Broom, and can form pools of bright yellow in late April.

Habitat - Prostrate Broom is confined to cliffs and coastal rocks, often in exposed areas, which might cause one to think that this is the reason for the flattened, wind-pruned appearance of the plant.

Comments - The seeds of this subspecies are said to breed true i.e. producing similar prostrate plants a few centimetres high, as opposed to the large upright shrubs of Common Broom. Many insects feed on this plant including the Chrysomelid beetle Gonioctena olivacea and its larva.