Brooms range from low spreading to upright shrubs, or even small trees. Typically yellow or white, pea-like flowers, but with hybridising there is a real range of colour available. Foliage is normally reduced, providing quite an see-through effect, until the profusion of flowers are produced.
The swathes of normally fragrant flowers of brooms are highly attractive to pollinating bumblebees and honeybees. Despite the presence of many complex (sometimes pharmacologically active) chemicals designed to protect the plant against being eaten, there are a large number of insects that are specialized in using it including weevils, micromoths and caterpillars of the green hairstreak butterfly. Some non-native species are becoming increasingly established in our countryside but as most of these derive from municipal plantings, growing them in our gardens is unlikely to add significantly to ecological harm.