The generic name bestowed by Linnaeus posthumously honoured the Reverend Adam Buddle (1662–1715), an English botanist and rector, at the suggestion of William Houstoun.

The International Code of Botanical Nomenclature has gradually changed to incorporate stricter rules about orthographic variants and as of the 2006 edition requires (article 60, particularly 60.5) that Linnaeus' spelling should be followed in this case.

[11] The colour of the flowers varies widely, from mostly pastel pinks and blues in Asia, to vibrant yellows and reds in the New World, while many cultivars have deeper tones.

As garden shrubs, buddlejas are essentially 20th-century plants, with the exception of B. globosa which was introduced to Britain from southern Chile in 1774 and disseminated from the nursery of Lee and Kennedy, Hammersmith.

The most popular cultivated species is Buddleja davidii from central China, named for the French Basque missionary and naturalist Père Armand David.

Other common garden species include the aforementioned B. globosa, grown for its strongly honey-scented orange globular inflorescences, and the weeping Buddleja alternifolia.

A number of agricultural organizations and governing authorities throughout the world have designated the plant as an invasive species or a noxious weed.

[17] Popular garden cultivars include 'Royal Red' (reddish-purple flowers), 'Black Knight' (very dark purple), 'Sungold' (golden yellow), and 'Pink Delight' (pure pink).

The listing below includes the names, still prevalent in horticulture, of many former Asiatic species sunk by the late Toon Leeuwenberg as Buddleja crispa and adopted as such in the definitive Flora of China.