The species name davidii honors the French missionary and explorer in China, Father Armand David, who was the first European to report the shrub.

Another botanist-missionary in China, Jean-André Soulié, sent seed to the French nursery Vilmorin, and B. davidii entered commerce in the 1890s.

However, as the distinctions of the former varieties are still widely recognized in horticulture, they are treated separately here: Buddleja davidii cultivars are much appreciated worldwide as ornamentals and for the value of their flowers as a nectar source for many species of butterfly.

A plant-evaluation manager at the Chicago Botanic Garden in Glencoe, Illinois (USDA Hardiness zone 5b) rated nearly 50 Buddlejia varieties and cultivars during a six-year trial period, summarizing in 2015 the characteristics of each and the study's findings.

[12] University studies have suggested that nectaring butterflies have greater preferences for some Buddleja cultivators than for others, with Lo & Behold 'Blue Chip' and 'Pink Delight' heading a list of eleven.

[14][15] Buddleja davidii has been designated as an invasive species or a "noxious weed" in a number of countries in temperate regions, including the United Kingdom, the Republic of Ireland and New Zealand.

[16] It is naturalized in Australia[17] and in many cities of central and southern Europe, where it can spread on open land, railway lines, urban areas and in gardens.

[20] A number of Buddleja cultivars have become available that have a variety of sizes and blossom colors and that are either sterile or produce less than 2% viable seed.

[20][23][25][26] The northwestern U.S. state of Oregon, which designated B. davidii as a "noxious weed" and initially prohibited entry, transport, purchase, sale or propagation of all of its varieties, amended its quarantine in 2009 to permit those cultivars when approved or when proven to be interspecific hybrids.

[30] Peter Podaras developed the "Flutterby" Buddleja series during the 2000s while at Cornell University's Department of Horticulture in Ithaca, New York and patented them in 2011.