Buddleja (; Buddleia; also historically given as Buddlea) is a genus comprising over 140 species of flowering plants endemic to Asia, Africa, and the Americas. The generic name bestowed by Linnaeus posthumously honoured Adam Buddle (1662–1715), an English botanist and rector, at the suggestion of William Houstoun. Houstoun sent the first plants to become known to science as buddleja (B. americana) to England from the Caribbean about 15 years after Buddle's death. Buddleja species, especially Buddleja davidii and interspecific hybrids, are commonly known as butterfly bushes and are frequently cultivated as garden shrubs. Buddleja davidii has become an invasive species in both Europe and North America.
Nomenclature
The botanic name has been the source of some confusion. By modern practice of botanical Latin, the spelling of a generic name made from Buddle would be Buddleia, but Linnaeus in his Species Plantarum of 1753 and 1754 spelled it Buddleja, with the long i between two vowels, common in early modern orthography. The pronunciation of the long i in Buddleja as j is a common modern error. 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.
Classification
The genus Buddleja is now included in Scrophulariaceae, having earlier been classified under Buddlejaceae (synonym: Oftiaceae) and Loganiaceae
Description
Of the approximately 140 species, nearly all are shrubs less than tall, but a few qualify as trees, the largest reaching . Both evergreen and deciduous species occur, in tropical and temperate regions respectively. The leaves are lanceolate in most species, and arranged in opposite pairs on the stems (alternate in one species, B. alternifolia); they range from long. The flowers of the Asiatic species are mostly produced in terminal panicles long; the American species more commonly as cymes forming small, globose heads. Each individual flower is tubular and divided into four spreading lobes (petals) about across, the corolla length ranging from around 10 mm in the Asiatics to 3–30 mm in the American species, the wider variation in the latter because some South American species have evolved long red flowers to attract hummingbirds, rather than insects, as exclusive pollinators.
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. The flowers are generally rich in nectar and often strongly honey-scented. The fruit is a small capsule about long and diameter, containing numerous small seeds; in a few species (previously classified in the separate genus Nicodemia) the capsule is soft and fleshy, forming a berry.
Distribution
The genus is found in four continents. Over 60 species are native through the New World from the southern United States to southern Chile, while many other species are found in the Old World, in Africa, and parts of Asia, but all are absent as natives from Europe and Australasia. The species are divided into three groups based on their floral type: those in the New World are mostly dioecious (occasionally hermaphrodite or trioecious), while those in the Old World are exclusively hermaphrodite with perfect flowers.
Cultivation and uses
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. Several species are popular garden plants and are commonly known as "butterfly bushes", owing to their attractiveness to butterflies, and have become staples of the modern butterfly garden; they are also attractive to bees and moths.
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. Several interspecific hybrids have been made, notably B. 'Lochinch' (B. davidii × B. fallowiana) and B. × weyeriana (B. globosa × B. davidii), the latter a cross between a South American and an Asiatic species.
thumb|right|upright=1.0|Budleja davidii self-sown along a railroad right-of-way at [[Düsseldorf, Germany (2016)]]
Some species commonly escape from the garden. B. davidii in particular is an extensive coloniser of dry open ground. In urban areas in the United Kingdom, it often self-sows on waste ground or old masonry, where it grows into a dense thicket. A number of agricultural organizations and governing authorities throughout the world have designated the plant as an invasive species or a noxious weed. It is frequently seen in the United Kingdom beside railway lines, on the sites of derelict factories and other buildings and, in the aftermath of World War II, on urban bomb sites. That earned it the popular nickname of "the bomb site plant".
List of species and naturally occurring hybrids
The many species of Buddleja have been the subject of much taxonomic contention. 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.
- Buddleja acuminata <small>Poir.</small>
- Buddleja agathosma <small>Diels</small>
- Buddleja × alata <small>Rehder & E.H.Wilson</small>
- Buddleja albiflora <small>Hemsl.</small>
- Buddleja alternifolia <small>Maxim.</small>
- Buddleja americana <small>L.</small>
- Buddleja anchoensis <small>Kuntze</small>
- Buddleja araucana <small>Phil.</small>
- Buddleja aromatica <small>Rémy</small>
- Buddleja asiatica <small>Lour.</small>
- Buddleja auriculata <small>Benth.</small>
- Buddleja axillaris <small>Willd. ex. Roem. et Schult.</small>
- Buddleja bhutanica <small>T. Yamaz.</small>
- Buddleja blattaria <small>J. F. Macbr.</small>
- Buddleja brachiata <small>Cham. & Schltdl.</small>
- Buddleja brachystachya <small>Diels.</small>
- Buddleja bullata <small>Kunth</small>
- Buddleja candida <small>Dunn</small>
- Buddleja cardanesii <small>Standl. ex E. M. Norman</small>
- Buddleja caryopteridifolia <small>W.W. Sm.</small>
- Buddleja cestriflora <small>Cham.</small>
- Buddleja chapalana <small>B. L. Rob.</small>
- Buddleja chenopodiifolia <small>Kraenzl.</small>
- Buddleja colvilei <small>Hook.f. & Thomson</small>
- Buddleja cordata <small>Kunth</small>
- Buddleja cordobensis <small>Griseb.</small>
- Buddleja coriacea <small>J.Rémy</small>
- Buddleja corrugata <small>M. E. Jones</small>
- Buddleja crispa <small>Benth.</small>
- Buddleja crotonoides <small>A. Gray</small>
- Buddleja cuneata <small>Cham.</small>
- Buddleja curviflora <small>Hook. & Arn.</small>
- Buddleja cuspidata <small>Baker</small>
- Buddleja davidii <small>Franch. (Butterfly bush)</small>
- Buddleja delavayi <small>Gagnep.</small>
- Buddleja diffusa <small>Ruíz & Pav.</small>
- Buddleja domingensis <small>Urb.</small>
- Buddleja dysophylla <small>(Benth.) Radlk.</small>
- Buddleja euryphylla <small>Standl. & Steyerm.</small>
- Buddleja fallowiana <small>Balf.f. & W.W.Sm.</small>
- var. alba <small>Sabourin</small>
- Buddleja farreri <small>Balf.f & W. W. Sm.</small>
- Buddleja filibracteolata <small>J. A. González & J. F. Morales</small>
- Buddleja forrestii <small>Diels</small>
- Buddleja fragifera <small>Leeuwenb.</small>
- Buddleja fusca <small>Baker</small>
- Buddleja globosa <small>Hope</small>
- Buddleja glomerata <small>H. L. Wendl.</small>
- Buddleja grandiflora <small>Cham. & Schltdl.</small>
- Buddleja hatschbachii <small>E. M. Norman & L. B. Sm.</small>
- Buddleja hieronymi <small>R. E. Fr.</small>
- Buddleja ibarrensis <small>E. M. Norman</small>
- Buddleja incana <small>Ruiz & Pav.</small>
- Buddleja indica <small>Lam.</small>
- Buddleja interrupta <small>Kunth.</small>
- Buddleja iresinoides <small>(Griseb.) Hosseus</small>
- Buddleja jamesonii <small>Benth.</small>
- Buddleja japonica <small>Hemsl.</small>
- Buddleja jinsixiaensis <small>R. B Zhu</small>
- Buddleja kleinii <small>E. M. Norman & L. B. Sm.</small>
- Buddleja lanata <small>Benth.</small>
- Buddleja limitanea <small>W. W. Sm.</small>
- Buddleja lindleyana <small>Fortune ex Lindl.</small>
- Buddleja lojensis <small>E. M. Norman</small>
- Buddleja longifolia <small>Kunth.</small>
- Buddleja longiflora <small>Brade</small>
- Buddleja loricata <small>Leeuwenb.</small>
- Buddleja macrostachya <small>Wallich ex. Benth.</small>
- Buddleja madagascariensis <small>Lam.</small>
- Buddleja marrubiifolia <small>Benth.</small>
- Buddleja megalocephala <small>Donn. Sm.</small>
- Buddleja mendozensis <small>Gillies ex. Benth.</small>
- Buddleja microstachya <small> E. D. Liu</small>
- Buddleja misionum <small>Kraenzl.</small>
- Buddleja montana <small>Britton</small>
- Buddleja myriantha <small>Diels.</small>
- Buddleja nitida <small>Benth.</small>
- Buddleja nivea <small>Duthie</small>
- Buddleja oblonga <small>Benth.</small>
- Buddleja officinalis <small>Maxim.</small>
- Buddleja paniculata <small>Wallich.</small>
- Buddleja parviflora <small>Kunth</small>
- Buddleja perfoliata <small>Kunth</small>
- Buddleja pichinchensis <small>Kunth</small>
- Buddleja polycephala <small>Kunth</small>
- Buddleja polystachya <small>Fresen.</small>
- Buddleja pulchella <small>N. E. Br.</small>
- Buddleja racemosa <small>Torr.</small>
- Buddleja ramboi <small>L. B. Sm.</small>
- Buddleja rufescens <small>Willd. ex Schultes & Schultes</small>
- Buddleja saligna <small>Willd.</small>
- Buddleja salviifolia <small>(L.) Lam.</small>
- Buddleja scordioides <small>Kunth</small>
- Buddleja sessiliflora <small>Kunth</small>
- Buddleja skutchii <small>C. V. Morton</small>
- Buddleja simplex <small>Kraenzl.</small>
- Buddleja soratae <small>Kraenzl.</small>
- Buddleja speciosissima <small>Taub.</small>
- Buddleja sphaerocalyx <small>Baker</small>
- Buddleja stachyoides <small>Cham & Schltdl.</small>
- Buddleja stenostachya <small>Rehder & E.H.Wilson</small>
- Buddleja sterniana <small>A. D. Cotton</small>
- Buddleja suaveolens <small>Kunth & Bouché</small>
- Buddleja subcapitata <small>E. D. Liu</small>
- Buddleja tibetica <small>W. W. Sm.</small>
- Buddleja thyrsoides <small>Lam.</small>
- Buddleja tubiflora <small>Benth.</small>
- Buddleja tucumanensis <small>Griseb.</small>
- Buddleja utahensis <small>Coville</small>
- Buddleja vexans <small>Kraenzl. & Loes. ex E. M. Norman</small>
- Buddleja × wardii <small>C.Marquand</small>
- Buddleja yunnanensis <small>Gagnep.</small>
Formerly placed here
- Cephalanthus glabratus <small>(Spreng.) K.Schum.</small> (as B. glabrata <small>Spreng.</small>)
Gallery
<gallery mode="packed" widths=160px heights=160px>
Image:Buddavii.jpg|B. davidii – Invasive species, here in an urban area
Image:Buddleja asiatica.jpg|Buddleja madagascariensis – flowers and foliage
File:Ibuddleiaigarata.jpg|Unidentified Buddleja species in Igarata, Brazil
File:Monarch Butterfly Flower.jpg|Monarch butterfly feeding on Buddleja in Connecticut
File:Buddleja officinalis with Red Admiral.jpg|Red Admiral butterfly feeding on Buddleja officinalis in January
</gallery>
RHS Award of Garden Merit
The following Buddleja species and cultivars are (2017) holders of the Royal Horticultural Society's Award of Garden Merit:
- B. alternifolia
- B. asiatica
- B. davidii 'Black Knight'
- B. davidii 'Blue Horizon'
- B. davidii 'Camkeep' =
- B. davidii 'Darent Valley'
- B. davidii 'Dartmoor'
- B. davidii 'Monum' =
- B. davidii 'Monite' =
- B. davidii 'Royal Red'
- B. davidii 'White Profusion'
- B. fallowiana var. alba
- B. globosa
- B. 'Lochinch'
- B. madagascariensis
- B. 'Miss Ruby'
- B. officinalis
- B. 'Pink Delight'
- B. 'West Hill'
- B. × weyeriana 'Sungold'
Monographs
Asiatic and African species
- Leeuwenberg, A. J. M. (1979) The Loganiaceae of Africa XVIII Buddleja L. II, Revision of the African & Asiatic species. H. Veenman & Zonen, Wageningen, Nederland.
North and South American species
- Norman, E. (2000). Buddlejaceae. Flora Neotropica, Vol. 81. New York Botanical Garden, USA.
Cultivated species and cultivars
- Stuart, D. (2006). Buddlejas. RHS Plant Collector Guide. Timber Press, Oregon, USA.
References
External links
- Buddleja globosa pictures from Chilebosque.
- Reference to nomenclature issue
