Buddleja davidii Franchet

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Credits

Andrew Large (2021)

Recommended citation
Large, A.T. (2021), 'Buddleja davidii' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/buddleja/buddleja-davidii/). Accessed 2022-05-18.

Genus

Common Names

  • Butterfly bush
  • Buddleia
  • Summer lilac
  • Sommerflieder
  • Orange-eyed butterfly bush

Synonyms

  • Buddleja davidii var. alba Rehder & E.H. Wilson
  • Buddleja davidii var. glabrescens Gagnepain
  • Buddleja davidii var. magnifica (E.H. Wilson) Rehder & E.H. Wilson
  • Buddleja davidii var. nanhoensis (Chittenden) Rehder
  • Buddleja davidii var. superba (Veitch) Rehder & E.H. Wilson
  • Buddleja davidii var. veitchiana (Veitch) Rehder & Bailey
  • Buddleja davidii var. wilsonii (E.H. Wilson) Rehder & E.H. Wilson
  • Buddleja shaanxiensis Z.Y. Zhang
  • Buddleja shimidzuana Nakai
  • Buddleja striata Z.Y. Zhang
  • Buddleja striata var. zhouquensis Z.Y. Zhang
  • Buddleja variabilis Hemsley

Other taxa in genus

Glossary

F2
The second generation of progeny from an original hybridisation event; derivatives from the generation.
Tibet
Traditional English name for the formerly independent state known to its people as Bod now the Tibet (Xizang) Autonomous Region of the People’s Republic of China. The name Xizang is used in lists of Chinese provinces.
glaucous
Grey-blue often from superficial layer of wax (bloom).
included
(botanical) Contained within another part or organ.
ovate
Egg-shaped; broadest towards the stem.
pubescent
Covered in hairs.
subspecies
(subsp.) Taxonomic rank for a group of organisms showing the principal characters of a species but with significant definable morphological differentiation. A subspecies occurs in populations that can occupy a distinct geographical range or habitat.
taxonomy
Classification usually in a biological sense.

Credits

Andrew Large (2021)

Recommended citation
Large, A.T. (2021), 'Buddleja davidii' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/buddleja/buddleja-davidii/). Accessed 2022-05-18.

Shrub 0.5–5 m tall. Branchlets subquadrangular, stellate-tomentose when young, later glabrescent. Leaves opposite or occasionally subopposite, shortly petiolate; stipules leafy, often only present on main branches, suborbicular, 1–6 mm long; petiole stellate-tomentose, 1–5 mm long; leaf blade narrowly ovate, narrowly elliptic, or very narrowly ovate, 4–20 × 0.3–7.5 cm, acuminate at the apex, cuneate at the base, margin serrate to subentire, upper surface glabrous, beneath white-tomentose with stellate hairs, often ageing brown. Inflorescence terminal, racemose or thyrsoid, long and rather narrow, 4–30 × 2–5 cm, rarely smaller, composed of mostly short-stalked, lax, many-flowered cymes, flowers all shortly pedicellate or sessile; lower bracts leaflike, others small and linear. Peduncle, branches, and pedicels stellate-pubescent. Calyx slender campanulate, 2–3.5 mm, outside stellate pubescent to glabrous; lobes narrowly triangular, 0.5–2 mm. Corolla lilac, violet to dark purple, sometimes white, with an orange-yellow throat, 0.8–1.4 cm, outside glabrous or stellate pubescent and/or with glandular hairs; tube narrowly cylindrical, 6–11.5 × 1–1.5 mm, inside pilose except at base; lobes orbicular, spreading, 1.5–3 × 1.5–3 mm, outside glabrous. Stamens inserted at or just below middle of corolla tube; anthers oblong, 0.8–1.2 mm; filaments very short 0.1–0.5 × as long as the anthers. Ovary oblong to ovoid, 1.2–2 × 0.8–1.1 mm, glabrous or minutely pubescent, sometimes with glandular hairs. Style as long as the stigma 0.5–1.5 mm; stigma clavate. Capsules brown, narrowly ellipsoid to narrowly ovoid, acute at apex, 5–9 × 1.5–2 mm, glabrous or sparsely stellate pubescent. Seeds ellipsoid, 2–4 × 0.5 mm, long winged at both ends. (Leeuwenberg 1979Li & Leeuwenberg 1996).

Distribution  China Gansu, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Sichuan, Xizang, Yunnan, Zhejiang Japan

USDA Hardiness Zone 5-10

RHS Hardiness Rating H6

Conservation status Not evaluated (NE)

Taxonomic note A number of Buddleja davidii varieties have been published (see the list of synonyms), but none of these fall outside the normal range of the variability within the species, and therefore are here reduced to synonyms following Leeuwenberg (1979).

Buddleja davidii is, for most people, the most familiar species in the genus, both as a selectively-bred garden ornamental and as a feral non-native and potentially invasive shrub in many temperate regions. In its wild state B. davidii is native to large areas of central and south China; possibly its native range includes Japan, although here it may have been introduced. Originally a plant of rocky slopes and forest edges, almost wherever it has been cultivated it has inevitably escaped and spread rapidly, colonising disturbed ground and urban waste-ground.

B. davidii is a very variable species, at one time named B. variabilis to reflect the diversity of growth habit, foliage, and flower form and colour. The species can be a small sub-shrub through to a large spreading shrub, or even occasionally a small tree with a trunk diameter of up to 30 cm. The bark is brown and deeply fissured. The foliage is also variable; plants may carry large, elliptic dark green leaves or small narrowly ovate and glaucous leaves, most types having a white tomentose underside. The species is usually semi-deciduous in temperate regions, with the level of foliage retained over the winter being dependent on both the conditions and the cultivar. Generally, the large leaves are lost in autumn and replaced by smaller, more pubescent leaves, which may be retained all winter. Within its native range flower colour is varied, with flowers ranging from purple to pale lilac, as well as a naturally occurring white form (Chen et al. 2014).

The species was originally introduced into Europe from Tibet in 1869 by the French-Basque missionary and plant collector Père David, for whom it is named. Another very early introduction, of seed obtained from Russian traders, was not considered of horticultural merit. A superior form was introduced to France in 1893 and was raised in the Jardin des Plantes, Paris, and by the nursery firm of Vilmorin; seed was later sent from France to the Royal Botanic Gardens, Kew. Between 1907 and 1910 the plant hunter E.H. Wilson collected B. davidii seed in Hubei and Sichuan provinces. B. davidii var. magnifica (sic.), propagated from seed sent back by Wilson, was thereafter widely grown in the UK. Another early introduction to the trade was made under the name B. davidii var. veitchiana, raised by the Veitch Nursery in England, also from a Wilson collection. Neither of these remain common in cultivation, although many of today’s garden varieties are descended from the seed collected by Wilson during these years (Tallent-Halsell & Watt 2009). At the time of Wilson’s collections and the naming of new varieties, a number of other varieties were already published. However, no varieties or subspecies are recognised by the current taxonomy, as none are considered to be sufficiently distinct from the species. (Leeuwenberg 1979).

As soon as superior forms were available the shrub quickly became much prized for both its large, highly scented blooms and as a nectar source for butterflies, and became widespread as a garden ornamental, but it soon developed a reputation for being a coloniser and even invasive. Once established, plants were able to set seed and thus escape from gardens into the wider landscape. Individual plants are able to produce thousands of tiny winged seeds which are carried on air currents, therefore the species is able to spread easily, particularly along roads and railway lines. The gravel ballast of railways in particular were an ideal habitat for the seedlings, which favour free drainage. Demolition sites, disturbed ground, old quarries, neglected buildings and forest clearings will play host to this Buddleia species, and it has become a familiar sight in many parts of Europe, all the more noticeable for the large bright summer flowers. Although there are costs associated with the removal of feral Buddleja, it is not usually considered a pernicious invasive in Europe (Tallent-Halsell & Watt 2009).

The situation is somewhat different in Oregon and Washington states in the US, and New Zealand, where B. davidii is considered an invasive species, and its spread and cultivation legally controlled. Oregon classifies it as a B Designated Weed and Washington as a C Noxious Weed (Young-Mathews 2011). In New Zealand, B. davidii has proved problematic in both natural habitats and pine plantations. Biological control by the regulated release of the Buddleia leaf-feeding weevil Cleopus japonicus has been trialled as method for controlling its impact and spread (Watson et al. 2001) and subsequenly there was a controlled release of the weevil (Watson, Withers & Heaphy 2011).

Once B. davidii was accepted as a valuable ornamental shrub in gardens selectively-bred cultivars of B. davidii started to appear. Two of the earliest, ‘Amplissima’ and ‘île de France’, originated from French nuseries; new cultivars were also being developed in the Netherlands, the UK and the USA. The pace of new cultivar introduction increased following WW2 and many of the older cultivars from this time remain popular and widespread today, for example ‘Royal Red’ and ‘Black Knight’, which both continue to receive the RHS Award of Garden Merit recognising their excellent garden performance (RHS Trials Office 2010). New garden varieties have continued to appear, and there has been an increase in breeding efforts in recent years; modern cultivars tend to be selected for bigger, brighter and more intensely coloured flowers. Smaller plants, selected for shorter internodes and well-branched habits, have proved popular for smaller gardens and containers, for example the BUZZ® series from Thompson and Morgan in the UK.

B. davidii has also been used to develop a number of hybrids with other species. The first reported garden hybrids were bred by Colonel Van Weyer at Corfe Castle, Dorset, UK during the Great War (van de Weyer 1920). The resulting cultivars included B. globosa × B. davidii F2 hybrids, known as B. × weyeriana and still widely cultivated today. The species has also been hybridised with B. fallowiana to develop the popular cultivars ‘Lochinch’ and ‘Westhill’ AGM (Stuart 2006; see B. fallowiana × davidii). The current fascination for miniature Buddleja has led to the development of complex multi-species hybrids with dwarf habits, and often coming with the added advantage of low or zero seed-set potentially making them suitable for cultivation in jurisdictions where B. davidii is legally defined as an invasive species.

B. davdii and plants derived from this species continue to be popular garden shrubs and the number and diversity of cultivars available seems only likely to increase. There are now in excess of two hundred named cultivars and hybrids of B. davidii, several recognised as excellent garden plants by being awarded the Royal Horticultural Soceity’s Award of Garden Merit. A large number of recent introductions have yet to appear in literature and many have yet to be fully tested in real garden situations. It would seem likely a number of these will disappear from catalogues and collections, as have some of the older cultivars still found in literature but now all but unobtainable in the nursery trade. Old favourites like ‘Black Knight’, ‘Royal Red’ and ‘White Profusion’ remain widely available, and their popularity is unlikely to be diminished by the newer introductions.

Below we list a selection of B. davidii cultivars (excluding its hybrids, which are considered elsewhere) which are representative of the range found in horticulture.


'African Queen'

A selection originating in 1959 at the Boskoop Nursery, the Netherlands by W. Schoemaker, which has dark flowers of a rich deep purple. The narrow flower panicles are up to 25 cm long, but are smaller than many modern cultivars. A large and tall plant, likely to reach 2 metres in height even after hard pruning, with dark green foliage, silvery beneath (Stuart 2006).


'Amplissima'

An old cultivar raised by the Lemoine nursery at Nancy, c. 1911 (Hatch 2018–2020). ‘Amplissima’ has large mauve inflorescences followed by dark purple seed capsules in the autumn; the foliage is dark green, turning a bluish grey in summer (Stuart 2006). One of the earliest named cultivars of B. davidii, it is now extremely rare in cultivation.


'Autumn Beauty'

Synonyms / alternative names
Buddleja davidii 'Clive Farrell'
Buddleja davidii 'Beijing'
Buddleja 'Clive Farrell'
Buddleja 'Beijing'

A cultivar arising from seed collected near to Beijing, ‘Autumn Beauty’ is distinguished by its late flowering habit, late August until October in the UK; its synonym ‘Clive Farrell’ honours the UK lepidopterist who selected the plant as a nectar source for migrating and late season butterflies. It’s a spreading and fast growing shrub with medium-green foliage. The inflorescences are fragrant and nectar-rich, and of a pink-lilac hue. Sometimes catalogued as an unknown species due to its unusual phenology, the flowers opening some six weeks later than is typical for the species, the plant is otherwise identical to B. davidii (Stuart 2006).


'Black Knight'

Awards
RHS AGM

‘Black Knight’ dates from c. 1959 and was selected by the renowned plant breeder Bonne Ruys of the Moerheim Nursery, the Netherlands. It is a large and vigorous cultivar, easily reaching 4 metres in height with an upright habit. The flowers are an intense dark purple, one of the darkest of all the Buddleias, with a pronounced yellow-orange eye. Although floriferous, the individual pancicles are quite small by modern standards, only about 5 cm in diameter and 20–25 cm long, but the colour has yet to be bettered (Stuart 2006). ‘Black Knight’ remains one of the most popular and widely available cultivars and has consistently been awarded the RHS AGM recognising its excellent garden performance (RHS Trials Office 2010).


'Blue Horizon'

Awards
AGM

Largely considered the best of the blue cultivars, ‘Blue Horizon’ was awarded a RHS Award of Garden Merit in 2010 (RHS Trials Office 2010). It is a large upright shrub of uncertain origin, although most extant plants are possibly derived from a single specimen grown at Cotswold Garden Flowers, Worcestershire, UK (B. Brown pers. comm.). The flower panicles are long and occasionally branched; the colour is a true blue. Foliage is dark green to somewhat glaucous. It remains relatively uncommon in cultivation compared to the inferior ‘Empire Blue’ (Stuart 2006).


'Bonnie'

A richly scented selection made by Dr Mike Dirr in the US and named for his wife. The flowers are a light lavender with a bright ornage eye and the foliage a dark grey-green (Hatch 2018–2020).


'Border Beauty'

Synonyms / alternative names
Buddleja davidii 'Boskoop Beauty'

‘Border Beauty’ was raised by Dutch nurseryman Henry Schiphorst at the Boskoop Nursery, Wageningen, the Netherlands and released to the trade in 1962. It is occasionally misnamed as ‘Boskoop Beauty’ due to its origin. ‘Border Beauty’ is a large upright shrub bearing large mauve-pink inflorescences; the foliage is dark green and the young stems are tinged purple (Stuart 2006).


'Boscranz'

Synonyms / alternative names
Buddleja davidii CRANRAZZ
Buddleja davidii REVE DE PAPILLON RED

See under REVE DE PAPILLON® Series.


'Buddma'

Synonyms / alternative names
Buddleja davidii MOONSHINE

MOONSHINE (‘Buddma’) was found as a chance seedling by Pieter van Manen of Ederveen, the Netherlands in 2006 and introduced by Plantipp. It is a small dense shrub, rarely exceeding 1.5 m in height, distinguished by its chartreuse yellow to lime-green foliage; the inflorescences are large and a bright pink-purple in colour (Hatch 2018–2020).


'Butterfly Heaven'

A relatively recent introduction from 2009, this arose as a seedling of ‘Pink Delight’ selected by Adrian Bloom in England. ‘Butterfly Heaven’ has an upright and compact habit, and is particularly floriferous. The flowers are a light lavender colour with a golden-orange centre (Hatch 2018–2020).


BUZZ™ Series

A series of smaller Buddleia developed by Charles Valin at Thompson and Morgan, UK, and released from 2009 beginning with BUZZ LAVENDER and BUZZ MAGENTA, with subsequent releases until 2016. As well as small size, they’ve been selected for a floriferous habit, larger flowers and, in the later releases, intense colours. They remain small in containers, up to 1 m, but will grow to 1.5 m or more when fully established in the ground. They are generally as hardy as the species. The Series carries trade designations in addition to a cultivar name, and some carry synonyms for different regions (RHS 2020; C. Valin pers. comm.).

  • ‘Tobudospin’ (BUZZ™ CANDY PINK; BUZZ™ SOFT PINK) Large, mid-pink conical inflorescence
  • ‘Tobud1202’ (BUZZ™ HOT RASPBERRY) Deep raspberry-cerise flowers, the last (thus far) to be released
  • ‘Harkstead Indigo’ (BUZZ™ INDIGO; BUZZ™ MIDNIGHT) Dark navy blue, rivals ‘Black Knight’ as the darkest of all cultivars
  • ‘Tobudivo’ (BUZZ™ IVORY) Cream-white flowers in large conical panicles
  • ‘Tobudviole’ (BUZZ™ LAVENDER; BUZZ™ VIOLET) An average lilac-lavender colour, but the blooms are particularly large for the size of plant
  • ‘Tobudpipur’ (BUZZ™ MAGENTA) Pink-purple flowers; the colour is not especially striking
  • ‘Tobudmagen’ (BUZZ™ MAGENTA IMPROVED) An improvement on the original release with brighter coloured flowers
  • ‘Tobudvelv’ (BUZZ™ RED; BUZZ™ VELVET) A very upright shrub which will grow taller than the rest of the BUZZ™ series, reaching 2 m tall but with a much narrower spread
  • ‘Tobudskybl’ (BUZZ™ SKY BLUE) With notably smaller and more glaucous leaves than other members of the series, BUZZ SKY BLUE has large blooms with densely packed flowers which open mauve and fade to a pleasing violet – not sky-blue as the name might suggest

'Darent Valley'

Awards
AGM

This chance seedling was discovered growing along the M20 motorway at Farningham, close to the Darent Valley in Kent, UK, by Gerald Roberts in 1989. It was subsequently brought into cultivation in 1992. It is a large, vigorous and upright cultivar growing to 2 metres if pruned, and with particularly showy upright panicles of bright white flowers. A great improvement on previous white forms, it was awarded the RHS AGM in 2010 (RHS Trials Office 2010, G. Roberts, pers comm.). Although currently the best form of any white-flowered B. davidii, this cultivar is still not widely available.


'Dartmoor'

Awards
AGM

‘Dartmoor’ is one of the most distinctive cultivars of B. davidii. It derives from a feral plant found in a ravine on Dartmoor, England, by a retired American gardener named Hayles, and introduced into horticulture in 1973. A very large and vigorous shrub, it can grow to a height and spread of 5 metres. The foliage is typical for the species, but the flowers are large and many-branched, unlike the usual single panicles of most forms. Flower colour is an unremarkable lilac-mauve. The inflorescences are so large and heavy they weigh down the ends of the branches, giving the mature plant an arching structure. Although a large, ungainly shrub, the impressive flowers are unparalleled in any other cultivar. It was awarded the RHS AGM in 1993, re-confirmed in 2010 (Stuart 2006; RHS Trials Office 2010) and remains widely available in the trade.


'Ellen's Blue'

Awards
AGM

An American cultivar which arose as a chance seedling of Buddleja ‘Lochinch’ in the garden of Ellen Hornig, Seneca Hill Perennials, New York. The foliage is somewhat glaucous and the flowers are of a rich violet-blue. With pruning it remains a manageable shrub of about 1.5 m tall (Stuart 2006). Following the Royal Horticultural Society’s Buddleja Euro-Trial, ‘Ellen’s Blue’ was recommended for an AGM in 2010 (RHS Trials Office 2010).


'Empire Blue'

An older cultivar, selected by K.A. Lucal and introduced by the Good and Reese nursery, Ohio, USA in 1941 (Hatch 2018–2020). The flowers are of a dark blue-violet, but are small compared to more recent selections, although the scent is particularly sweet. The shrub is tall and upright, growing in excess of 2 m; the foliage is typical for the species (Stuart 2006). ‘Empire Blue’ was awarded the RHS AGM in 1993, but is now considered inferior to more recent cultivars, in particular to ‘Blue Horizon’ AGM, which has larger panicles of a deeper and truer blue. Therefore, ‘Empire Blue’ has been added to the RHS ‘Sunset List’ to rescind its AGM (RHS Trials Office 2010). However, ‘Empire Blue’ remains one of the most common and popular cultivars on both sides of the Atlantic.


ENGLISH BUTTERFLY Series

A series of smaller Buddlejas raised by Elizabeth Keep at the East Malling Research Station, Kent, UK and in her own garden following her retirement in 1983 (Stuart 2006; Hatch 2018–2020).

  • ‘Adokeep’ (ADONIS BLUE) Dark navy blue flowers, one of the finest colours of any Buddleja. Although remaining small, about 1.5 m in maximum height, the growth habit can be lax
  • ‘Camkeep’ (CAMBERWELL BEAUTY) Large deep pink-purple inflorescences which are heavily branched, making the plant resemble a miniature ‘Dartmoor’. It can look magnificent in full flower and was awarded the RHS AGM in 2010. However, it is prone to reversion to both single panicles and an inferior colour (pers. obs.)
  • ‘Markeep’ (MARBLED WHITE) A smaller white-flowered cultivar. The inflorescences are large and bright, and the panicle has conspicuous bracts
  • ‘Peakeep’ (PEACOCK) A very upright shrub reaching only 1.5 m in height, with large bright pink flowers
  • ‘Pyrkeep’ (PURPLE EMPORER) A very floriferous selection with deep purple flowers and small, dark-green leaves. Will not exceed 2 m height

'Fascination'

Synonyms / alternative names
Buddleja davidii 'Fascinating'

‘Fascination’ was selected by Paul Schmidt at Youngstown, Ohio, in 1940. It is a vigorous grower, reaching 2.5 m even with hard pruning. The large, upright panicles are pink-lilac to orchid pink in colour. ‘Fascination’ is also notable as one of the cultivars used to breed the very popular hybrid ‘Pink Delight’ (Hatch 2018–2020; Stuart 2006).

The name has also been misspelt ‘Fascinating’, although Stuart (2006) lists this as a separate cultivar.


'Glasnevin Hybrid'

Synonyms / alternative names
Buddleja davidii 'Glasnevin'
Buddleja davidii 'Glasnevin Blue'

This cultivar is named for the location of the National Botanic Gardens of Ireland (Glasnevin, Co. Dublin), where it is believed to have originated some time prior to 1952 (Nelson 2000). Its appearance strongly suggests it is derived from the ‘Nanhoensis’ type of B. davidii (pers. obs.). Stuart (2006) incorrectly describes it as a hybrid of B. fallowiana and B. davidii originating from Lochinch Castle, Scotland.

‘Glasnevin Hybrid’ is a restrained shrub of 1.5 metres height and spread with small and narrow grey foliage. The flowers are arranged in the typical panicles of the species and are a pleasant light china-blue, each with a small orange eye (Stuart 2006). It is a delicate cultivar and, although fully hardy, takes several years to establish.


'Gulliver'

A relatively recent introduction (2006) originating from a cross of ‘Pink Delight’ (seed parent) and ‘Nanho White’ (pollen parent) made at the East Malling Research Station, Kent, UK by Kenneth Tobutt. ‘Gulliver’ is a compact shrub up to 2 m in height which produces huge, balloon-like inflorescences of a lilac pink in the summer months. The cultivar is unrivalled for size of the blooms. (Genesis Plant Marketing, pers. comm., CPVO application no.20071072).


'Harlequin'

Synonyms / alternative names
Buddleja davidii 'Royal Red Variegata'

A variegated sport of ‘Royal Red’, the leaves have narrow cream-white margins; the flowers however are slightly duller than in ‘Royal Red’. Introduced in 1964, it has become less popular in recent years due to its susceptibility to spider mites and a propensity for reversion (Stuart 2006). Nevertheless, ‘Harlequin’ remains the most widely disseminated and obtainable variegated form of B. davdii. Other variegated forms discussed here include the cultivars ‘Notbud’, ‘Thia’, ‘Watflor’ and ‘White Harlequin’.


'Île de France'

One of the earliest cultivars to be named, it was introduced by Auguste Nonin at Chatillon-sous-Bagneux, France c. 1930. It is a large shrub of 3 m height and spread. The flowers are purple-violet, sometimes fading to a paler violet after opening (Stuart 2006). It has lost popularity in recent years as the flowers are unremarkable compared to more recent introductions. After so long a history, it’s possible the name is now being applied to several different plants (pers. obs.).


'Les Kneale'

Discovered by Les Kneale on the Isle of Man, the plant which bears his name is a large spreading shrub with pale green leaves. The flowers are a very pale lilac to almost white (Stuart 2006). The colour of the corolla can be variable and has shown some drift following rounds of vegetative propagation, with some clones displaying more conspicuously lilac blooms (pers. obs.).


'Lonplum'

Synonyms / alternative names
Buddleja davidii SUGAR PLUM

Bred by Peter Moore, Hampshire, UK, SUGAR PLUM is a cross of ‘Royal Red’ and ‘Summer Beauty’. It is a medium-sized cultivar with an upright and dense habit; the foliage is dark green. The inflorescences are reasonably long, up to 30 cm, and of a good cerise-red colour (P. Moore pers. comm.). SUGAR PLUM compares favourably with other recent cultivars and hybrids that come close to true red (pers. obs.).


'Mongo'

Synonyms / alternative names
Buddleja davidii NANHO BLUE
Buddleja davidii PETITE INDIGO
Buddleja davidii NANHO PETITE INDIGO

Originating from the Monrovia Nursery, California, USA, in the 1980s, ‘Mongo’ has acquired several trade names, and is most commonly known as NANHO BLUE. It is derived from the ‘Nanhoensis’ form of B. davidii and has small, greyish dark green leaves. The growth habit can be somewhat straggly, so it benefits from hard spring pruning. The inflorescences are long and narrow, and the flower colour is blue to blue-violet (Stuart 2006). Awarded the RHS AGM in 2002, this cultivar was added to the ‘Sunset List’ in 2010 for the award to be rescinded (RHS Trials Office 2010).


'Monite'

Synonyms / alternative names
Buddleja davidii NANHO WHITE
Buddleja davidii NANHO ALBA
Buddleja davidii PETITE SNOW

Also raised at the Monrovia Nursery (California, USA) as early as 1967, NANHO WHITE is a small dense shrub of less than 2 metres with narrow grey-green foliage. The inflorescence is a wide and conical panicle of pure white flowers with a yellow-orange eye. It is still one of the best white-flowered cultivars available, and in recognition of its superior garden performance was awarded the RHS AGM in 2010 (RHS Trials Office 2010).


'Monum'

Synonyms / alternative names
Buddleja davidii NANHO PURPLE
Buddleja davidii NANHO PETITE PLUM
Buddleja davidii PETITE PLUM

Awards
AGM

‘Monum’, far better known as NANHO PURPLE, is a cross of B. davidii ‘Nanhoensis’ and ‘Royal Red’, backcrossed with ‘Royal Red’, and was introduced by the Monrovia Nursery, California, USA. It is a smaller cultivar, but quite vigorous, rarely exceeding 2 m in height. The foliage is smaller than average, but not as narrow or glaucous as that of NANHO BLUE. It is very free flowering with short (15–25 cm) panicles of bright purple flowers. Awarded the RHS AGM in 2002, re-confirmed in 2010 (RHS Trials Office 2010).


'Nanhoensis'

Synonyms / alternative names
Buddleja davidii var. nanhoensis

Although once described as a subspecies and a variety, it is here reduced to only cultivar status in accordance with the taxonomy of Leeuwenberg (1979). ‘Nanhoensis’ arose from a 1914 Reginald Farrer collection from Gansu, north-central China, and has remained in cultivation to the present day. It is a small, compact shrub rarely exceeding 1.5 m in height. The foliage is small, narrow and glaucous; the inflorescences however are typical for the species and pale lilac in colour (Clarke 1988).


'Notbud'

Synonyms / alternative names
Buddleja davidii MASQUERADE

A sport of ‘Harlequin’, which this cultivar resembles in most details, introduced by Notcutt’s Nurseries in 1992. It is reputedly less prone to reversion and the variegation is considered a little more marked (Stuart 2006), however, it has neither proved more popular nor become more widespread than its antecedent.


'Orchid Beauty'

A restrained cultivar growing to about 1.5 m tall, with a rounded habit. The foliage is felted and almost white on emerging, but becoming dark green once mature. The long inflorescences are of a clear lavender-pink and are sweetly scented. It should not be confused with the American cultivar ‘Orchid’ (Stuart 2006).


'Orpheus'

Raised at The Lavender Garden, Gloucestershire, UK, ‘Orpheus’ is a large upright shrub with dark green foliage. The large showy inflorescences are a good dark blue. This cultivar is distinguished by each flower having a bright white ring around the orange-red eye (A. Bullock, pers. comm.).


'Peace'

‘Peace’ is a vigorous white-flowered cultivar of unknown origin introduced into cutivation to commemorate the end of WW2. It grows to 2 m height with a dense, rounded habit. The panicles of white flowers are up to 30 cm in length, but have a tendency to fade to messy brown (Stuart 2006). ‘Peace’ is still widely cultivared in Europe and available from several specilist nurseries.


'Pink Pearl'

An older European cultivar, which grows to 3 m with grey-green foliage. The inflorescences are a lilac pink and the flowers densely packed on the panicle. Once the only choice for a true pink, ‘Pink Pearl’ has now been superseded by more modern, showy cultivars such as ‘Pink Delight’. (Stuart 2006). Consequently, ‘Pink Pearl’ is now relatively uncommon in cultivation.


'Pink Spread'

Synonyms / alternative names
Buddleja davidii 'Pink Spreader'

A medium sized shrub of Dutch origin with medium green leaves typical of the species, ‘Pink Spread’ grows wider than tall, to 3 m across. The growth is not as vigorous and lush as many other cultivars. The deep pink flowers have a cherry-red eye. Despite being one of the most striking colours among the older cultivars, ‘Pink Spread’ has not proved popular, most likely because of its inferior growth habit (Hatch 2018–2020; Stuart 2006).


'Pixie Blue'

Synonyms / alternative names
Buddleja davidii 'Dart's Papillon Bleu'

An older cultivar from the Dart’s Nursery in the Netherlands, it is a large vigorous shrub with attractive greyish foliage (Stuart 2006). The inflorescence is light blue and said to resemble a pixie hat in shape. At the recent RHS Euro-trial, ‘Dart’s Papillon Bleu’ and ‘Pixie Blue’ were submitted separately, but they proved to be one and the same (RHS Trials Office 2010).


'Pixie White'

A small, rounded shrub with fresh green narrow foliage. The long flower panicles carry bright white flowers (Stuart 2006).


'PMoore14'

Synonyms / alternative names
Buddleja davidii BERRIES AND CREAM

A very recent introduction from Peter Moore of the Longstock Nursery, Hampshire, UK, BERRIES AND CREAM is a seedling of ‘Royal Red’. Smaller in stature than its parent plant, the most notable (and possibly unique) feature is the bi-coloured inflorescence, which is a mixture of white, maroon, and maroon-speckled-white flowers (P. Moore, pers.comm.).


'Red Plume'

‘Red Plume’ is an American cultivar of undocumented origin. It is a very vigorous and particularly tall cultivar reaching over 3 m in height. The flower panicles are an impressive 30–40 cm long. The colour is a rich and velvety red-purple, similar to ‘Royal Red’. This cultivar is currently only commonly available on North America (Stuart 2006; Hawke 2015).


REVE DE PAPILLON® Series

REVE DE PAPILLON® (literally ‘Butterfly’s Dream’) is a series of cultivars, the first three bred in France at the Pepinieres Minier nursery, Beaufort-en-Vallée. Later introductions have been sourced from Ball Horticultural, USA. In order of introduction, the series currently consists of five cultivars:

  • ‘Minpap’ (REVE DE PAPILLON PINK) The first to be introduced, with large lilac-pink blooms on a relatively compact shrub reaching about 2 m height and spread; the foliage is grey-green
  • ‘Minpap2’ (REVE DE PAPILLON WHITE) Similar to REVE DE PAPILLON PINK in form and foliage, but with large white inflorescences
  • ‘Minpap3’ (REVE DE PAPILLON BLUE) The third introduction with large violet-blue flowers
  • ‘Boscranz’ (REVE DE PAPILLON RED; CRANRAZZ) Developed by Ball Horticultural and released as CRANRAZZ in the UK and USA, this was renamed for Europe and sold under the REVE DE PAPILLON name. A compact shrub, it has bright cranberry-pink flowers
  • ‘Bosjerry’ (REVE DE PAPILLON LAVENDER) Developed by Ball Horticultural, and sold under the REVE DE PAPILLON name in Europe. Again, a compact shrub with large lavender-blue flowers

'Royal Red'

Synonyms / alternative names
Buddleja davidii 'Red Admiral'
Buddleja davdii 'Pixie Red'

‘Royal Red’ is an older cultivar, originating from America. It was raised by Karle A. Lucal, introduced by the Good & Reese nursery, Ohio, USA and patented in 1942 (Hatch 2018–2020). It forms a large shrub with dark green foliage. The inflorescences are long and narrow, and of a uniform rich maroon colour; the usual yellow eye of the individual flowers is much reduced compared to other cultivars, adding to the intensity of the flower colour. Introduced into the UK after WW2, ‘Royal Red’ has become popular and widespread and remains one of the most recommended Buddleias. In recognition of its performance and excellent flower-colour, ‘Royal Red was accorded the RHS Award of Merit in 1950, reaffirmed (as the AGM) in 1993 and 2010 (RHS Trials Office 2010).

Described in Stuart 2006 as a separate cultivar, ‘Pixie Red’ is a clone of ‘Royal Red’. Plants labelled as ‘Pixie Red’ from several sources were grown at the Longstock Nursery (Hampshire, UK) and by the current author, and these proved to be indistinguishable from ‘Royal Red’. (P. Moore, pers. comm.; pers. obs.).


'Summerhouse Blue'

‘Summerhouse Blue’ is a cultivar propagated by Peter Moore from a volunteer seedling found growing near the summer house at the Longstock Nursery, Hampshire. UK. A fairly restrained shrub with a height and spread of 2 m, it has attractive grey-green foliage and china-blue inflorescences, each flower with a very small orange eye (Stuart 2006).


'Thia'

Synonyms / alternative names
Buddleja davidii SANTANA
Buddleja davidii 'Sultana'

SANTANA arose as a sport of ‘Royal Red’, selected by Rod Dransfield at Knaresborough, England, and introduced in 1997. The flowers are maroon-purple, but are slightly less rich compared to ‘Royal Red’. The foliage has an irregular variegation, and mostly consists of light green leaves with a wide bright yellow margin. It grows to height of 2 m and is less vigorous than ‘Royal Red’ (Hatch 2018–2020; Stuart 2006).


'Watflor'

Synonyms / alternative names
Buddleja davidii FLORENCE
Buddleja davidii 'Variegata'

A variegated selection of Buddleja davidii introduced by the Stone Green Nursery, Ashford, UK (Hatch 2018–2020). As with many variegated forms it is comparatively slow-growing, but will reach up to 2.5 m once mature. The small leaves are grey-green at the centre with a wide and irregular cream to pale-yellow margin, and are particularly eye-catching in the winter months if the weather remians mild. The flowers are an unremarkable pale violet-blue.


'White Ball'

‘White Ball’ was developed at Horticultural Research International, Boskoop, the Netherlands and released around 1993. The first truly dwarf cultivar to be developed, ‘White Ball’ has a congested growth habit with short internodes; it grows to only 1–1.5 m in height and spread if pruned hard in spring, but does not exceed 2 m if left unpruned. The relatively small panicles consist of yellow-eyed pure white flowers. The foliage is grey-green and narrow, as is typical for cultivars derived from the ‘Nanhoensis’ form (Hatch 2018–2020; Stuart 2006).


'White Bouquet'

One of the older white cultivars, ‘White Bouquet’ was raised by Hungarian émigrée Sigmund Tarnok at his New Orleans nursery and introduced by Jackson & Perkins Co. c. 1942. A large cultivar growing in excess of 3 m tall and broad, it has arching branches with terminal inflorescences often 30 cm or more long. The flowers are white with very small yellow eyes and the foliage is grey-green. Although attractive at the beginning of flowering, the flowers fade to brown and die messily (Hatch 2018–2020; Stuart 2006).


'White Cloud'

An older established cultivar of unrecorded origin, ‘White Cloud’ has yellow-eyed white flowers arranged in long panicles, which tend to turn an ugly brown as they fade. The foliage is lighter-green and slightly glaucous, the leaves closest to the terminal inflorescences are particularly narrow and somewhat misshapen (Stuart 2006).


'White Harlequin'

Buddleja davidii ‘White Harlequin’ is a variegated cultivar of unrecorded origin, and may have arisen independently several times. The leaves have wide cream-white margins similar to the purple-flowered ‘Harlequin’. The white-flower panicles are small and the overall the shrub lacks vigour, only growing to 1–1.5 m height/spread. It has a reputation for both reversion and for being difficult to keep alive (Stuart 2006).


'White Profusion'

Awards
AGM

‘White Profusion’, introduced to commerce in 1945, has proved to be one of the most popular and successful of the white-flowered cultivars, and remains so to this day. Accordingly, it was awarded the RHS AGM in 1993, reaffirmed in 2010 at the conclusion of the recent Buddleja Euro-trial at Wisley, UK (RHS Trials Office 2010). More compact than some other white cultivars, ‘White Profusion’ forms a well-branched shrub 1.5–2 m height with light green foliage. The flowers are said to be larger on plants that have been hard-pruned; in common with many other white Buddleja, the flowers tend to look messy as they fade (Stuart 2006).