Accepted Scientific Name: Euphorbia umbellata cv. Rubra hort.
Synadenium grantii f. rubrum (Euphorbia umbellata cv. Rubra) Photo by: © Plantemania
Origin and Habitat: Garden origin.
Synonyms:
See all synonyms of Euphorbia umbellata
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Accepted name in llifle Database:Euphorbia umbellata (Pax) BruynsEuphorbia World 3: 5 2007Synonymy: 6
Cultivars
(1):
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Common Names include:
ENGLISH: Red African Milk Bush, Red African Milkbush
SAKHA (Саxа Тыла): Синадениум Гранта "Рубра"
Description: Euphorbia umbellataSN|23046]]SN|23046]] best known in cultivation as Synadenium grantiiSN|23048]]SN|23048]] is a thornless semi-succulent, evergreen shrub or small tree, erect, richly branched from near the base and in its habitat becoming up to 3,5(-10) m in height with an equal spread. It is widely grown in the tropics for its giant fleshy leaves as an ornamental and hedge or cover plant and under glass in colder regions.
Red form: The red leafed form Euphorbia umbellataSN|23046]]SN|23046]] cv. Rubra has giant wine red or bronze red leaves and is the most common in cultivation. The plant is quite variable and comes in several colour variants, at one extreme we have plants with almost homogeneous reddish-purple leaves with occasional green spots, and the reverse of that is apple-green with reddish spots, but all intermediate graduation of red and green are possible. All this plant are variously named as 'Rubrum', 'rubra', 'Ruby', "rubrovariegata", or "var. rubrum". The various names all do seem to refer to the same plant; and are applied to the green plant with red spots, too, so make sure you see the plant (or a picture) before you buy, but the care for each is identical.
Stem: Main stem up to 12 or 15 cm thick branching from the base, with the bark of the older parts pale greyish. Younger branches, round, cylindrical, terete, glabrous, exuding milky sap, rubbery green, purplish-green or wine-coloured, and somewhat fleshy, 8-20 mm thick becoming woody and thickening with age.
Leaves: Crowded at the tips, slightly alternate, simple, thinly fleshy, obovate, obovate-spatulate, or oblanceolate with obtuse, subacute or apiculate tip,14-20 cm long and 2,5-7 cm wide sessile or gradually tapering from above the middle into a short stout petiole approximately 8 mm long, sparsely hairy towards the base, glabrous on both sides, reticulately veined with darker green with prominent midribs rounded beneath, uniformly wine red or variously mottled in green, paler beneath. Margins entire, flat or lightly wavy.
Inflorescences: Axillary and terminal, with 2 - 5 lax cymes, 7–15 cm long (including the 3-5 cm long peduncle), 5-10 cm broad, 2- to 6-forkedt hinly pubescent with spreading hairs on the upper part, glabrous below. Bracts 1 - 3 cm long, reddish-green subquadrate, very obtuse or subtruncate, entire, minutely pubescent.
Flowers (cyathia): Small and inconspicuous, bisexual or entirely male, broadly funnel-shaped or saucer-shaped, 6.5 mm in diameter, and 2 mm deep, brownish-red cyathia, in a small cup with a rim of nectar glands which are c. 1 mm wide, deeply furrowed and crimson pubescent on the basal part. Ovary puberulous, or pubescent. Lobes wholly overtopping the rim, glabrous. Perianth scarcely more than a mere truncate or minutely 3-lobed rim. Style 2 mm long connate at the basal half, deeply bifid above: Stigmas diverging-recurved.
Blooming season: Winter or early spring.
Fruits: 7 x 8 mm, pubescent, red, pedicel ± 5 mm long.
Seeds: Ovoid, 2.5 x 2 mm, minutely tuberculate, caruncle rudimentary.
Subspecies, varieties, forms and cultivars of plants belonging to the Euphorbia umbellata group
Bibliography: Major references and further lectures
1) Forest & Kim Starr “Synadenium grantii (African milkbush)”. Plants of Hawaii. <http://www.starrenvironmental.com>. Web. 27 Sep. 2014.
2) Umberto Quattrocchi “CRC World Dictionary of Medicinal and Poisonous Plants: Common Names, Scientific Names, Eponyms, Synonyms, and Etymology” (5 Volume Set) CRC Press, 03/May/2012
3) Nellie Neal “Gardener's Guide to Tropical Plants: Cool Ways to Add Hot Colors, Bold Foliage, and Striking Textures” Cool Springs Press, 15/Aug/2012
4) J. G. Baker, with additions by C. H. Wright. “Flora of Tropical Africa” Vol 6 1913
5) Urs Eggli “Illustrated Handbook of Succulent Plants: Dicotyledons” Springer Science & Business Media, 2002
6) George E. Burrows, Ronald J. Tyrl “Toxic Plants of North America” John Wiley & Sons, 15/Oct/2012
7) Wikipedia contributors. "Euphorbia grantii." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 11 Mar. 2013. Web. 5 Oct. 2014.
8) Verdourt, Bernard; E.C. Trump and M.E. Church “Common poisonous plants of East Africa.” London: Collins. 1969
9) Govaerts, R., Frodin, D.G. & Radcliffe-Smith, A. “World Checklist and Bibliography of Euphorbiaceae (and Pandaceae).” 2000
Leaves at Plants Alive Haiku, Maui, Hawaii (USA). June 09, 2009. (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Synadenium grantii f. rubrum (Euphorbia umbellata cv. Rubra) Photo by: Valentino Vallicelli Synadenium grantii f. rubrum (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Leaves at Enchanting Floral Gardens of Kula, Maui, Hawaii (USA). April 30, 2009. (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Leaves at Plants Alive Haiku, Maui, Hawaii (USA). June 09, 2009. (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Habit at Plants Alive Haiku, Maui, Hawaii (USA). June 09, 2009. (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Leaves at Plants Alive Haiku, Maui, Hawaii (USA). June 09, 2009. (Euphorbia umbellata cv. Rubra) Photo by: Forest Starr & Kim Starr Send a photo of this plant.The gallery now contains thousands of pictures, however it is possible to do even more. We are, of course, seeking photos of species not yet shown in the gallery but not only that, we are also looking for better pictures than those already present.
Read More... Cultivation and Propagation: Euphorbia umbellataSN|23046]]SN|23046]] (Synadenium grantiiSN|23048]]SN|23048]]) is very suited to growing on sunny terraces of warm areas need full sun to light shade with a very well drained soil mix with sand or perlite with small gravel added to ensure good drainage. Water them thoroughly and allow to dry before watering again. Fertilize the plants only once during the year with a balanced fertilizer.
Maintenance: The size of the plants is easily controlled by container size. The most important thing about growing these plants is be very careful not to over water them.
Propagation: Cutting and seed. The fresh cuts should be dipped in charcoal dust to stop the leaking of milky sap and should be struck in sand to root.
Warning: The latex is extremely irritant and can cause contact dermatitis. All plants parts are considered very poisonous. This one should not be grown around small children or animals that like to eat plants and be very careful to avoid the wounded surfaces when repotting or trimming up unwanted growth because of the corrosive milky sap.
Symptoms: Immediate or delayed irritation (burning, redness, blisters, swelling) to skin and eyes following contact with milky latex; ingestion causes irritation of lips, tongue, and throat.
Toxic Principle: Diterpene esters.
Severity: Highly toxic, maybe fatal if eaten. Skin irritation severe.