Euphorbia lactea Haw. (1812) is a succulent shrub from Sri Lanka that has become one of the most commercially transformed plants in the Euphorbia genus. In its typical form, it is a candelabra-shaped shrub with distinctive white-mottled, three-angled stems known as mottled spurge or dragon bones. But it is the extraordinary crested and variegated mutants — sold worldwide as “coral cactus,” “White Ghost,” and a kaleidoscope of coloured fan-shaped forms — that have turned Euphorbia lactea into a horticultural phenomenon. So commercially significant are these cultivated forms that CITES has explicitly exempted them from regulation, making Euphorbia lactea one of only three Euphorbia species to receive such a distinction. The latex contains phorbol-type diterpene esters, placing it among the more toxicologically significant members of the genus.
Taxonomy and Nomenclature
Euphorbia lactea was named and described by the English botanist Adrian Hardy Haworth in 1812, in his Synopsis Plantarum Succulentarum. The specific epithet lactea, from the Latin lac (“milk”), refers to the copious white latex exuded when the stems are cut — a characteristic shared by many euphorbias but particularly prominent in this species.
Within the genus Euphorbia, the species is classified in subgenus Euphorbia, section Euphorbia, alongside the other succulent candelabra-forming species.
According to Plants of the World Online (POWO, Kew), Euphorbia lactea has one synonym: Euphorbia lactea Roxb. (1832), which is nomenclaturally illegitimate (nom. illeg.) as a later homonym — the Indian botanist William Roxburgh independently described the same species under the same name, but Haworth’s 1812 publication has priority.
The native range given by POWO is Sri Lanka — a surprisingly narrow endemic origin for a plant now found across the tropics. The species has been introduced and is widely naturalised or cultivated in the Bahamas, Bangladesh, the Comoros, Cuba, the Dominican Republic, Ecuador, Hawaii, India, the Leeward Islands, Pakistan, Puerto Rico, the Society Islands, the southwest Caribbean, Thailand, Trinidad and Tobago, the Tuamotu Archipelago, the Tubuai Islands, the Venezuelan Antilles, and the Windward Islands.
Common names: mottled spurge, milkstripe euphorbia, dragon bones, candelabra spurge, candelabra cactus, candelabra plant, false cactus, hatrack cactus, elkhorn, frilled fan.
Description and Morphology
Euphorbia lactea is an erect, spiny, succulent shrub growing up to five metres tall, forming a dense candelabra-like silhouette of ascending branches. The overall habit is somewhat more compact and angular than the larger African tree euphorbias.
Stems
The stems are succulent, 3–5 cm in diameter, and constricted into oblong segments. They display a triangular or rhombic cross-section — typically three-sided, occasionally four-sided — with slightly winged, sinuate (wavy) ribs. The distinctive feature that gives the species its common name “mottled spurge” or “milkstripe euphorbia” is the mottled white-on-green patterning of the stems: irregular bands and streaks of whitish-green tissue on a darker green background, creating a marbled or milky appearance.
Spines
The spines are stipular, paired, widely divergent along the rib margins, and measure 2–6 mm long. They are sharp but small — much less formidable than the spines of Euphorbia ammak or Euphorbia abyssinica. On older stems, the spines may persist but become less prominent.
Leaves
The leaves are rudimentary, circular, reddish, up to approximately 3 mm in diameter, sessile, and deciduous — dropping almost immediately after emergence. In practical terms, Euphorbia lactea is essentially a leafless plant year-round, relying entirely on stem photosynthesis. This distinguishes it from Euphorbia trigona, which retains conspicuous teardrop-shaped leaves for extended periods.
Flowers and Fruits
Unlike Euphorbia trigona, the typical green form of Euphorbia lactea does flower in cultivation, though infrequently and unpredictably. The cyathia are small, yellowish-green, and appear along the upper ridges of the stems. The fruits are small, three-lobed capsules typical of the genus.
A Sri Lankan Endemic Gone Pantropical
The POWO-confirmed native range of Euphorbia lactea — restricted to Sri Lanka — is biogeographically remarkable. While most large candelabra euphorbias are concentrated in Africa and the Arabian Peninsula, Euphorbia lactea represents the genus’s succulent tree lineage in South Asia, where it occurs in seasonally dry tropical forest and scrubland habitats.
From this narrow island origin, Euphorbia lactea has become one of the most widely distributed cultivated euphorbias on Earth. It was introduced across South Asia (India, Bangladesh, Pakistan, Thailand) at an early date, likely through trade routes, and subsequently spread to the Caribbean, Central America, the Pacific Islands, and Hawaii. In many tropical regions, it has naturalised in disturbed habitats and is commonly used as a living fence and hedge plant — its spiny stems and caustic latex making it an effective deterrent to both livestock and humans.
This pantropical distribution, combined with its ancient introduction to the Indian subcontinent, led to considerable taxonomic confusion. Roxburgh’s 1832 description of the species from India — under the same name Haworth had already published in 1812 — reflected the assumption that the plant was native to India rather than introduced from Sri Lanka.
The Cultivar Revolution: Cristata, ‘White Ghost,’ and the Coral Cactus
No species of Euphorbia has generated a more diverse and commercially successful array of cultivated forms than Euphorbia lactea. Three major mutation categories have been exploited by growers:
1. Forma cristata — The Crested Forms
Fasciation — a developmental mutation that causes the growing point to become a line rather than a point — transforms the columnar stems of Euphorbia lactea into flattened, undulating, fan-shaped crests that resemble ocean coral, brain tissue, or ruffled fabric. This crested form (Euphorbia lactea f. cristata) is the basis of the universally popular “coral cactus” or “Frankenstein cactus” of the houseplant trade.
Because crested tissue grows slowly and often has a poor root system, it is almost universally grafted onto a rootstock of Euphorbia neriifolia (or occasionally Euphorbia canariensis or Euphorbia resinifera). The grafting technique involves cutting a V-shaped notch into the rootstock and fitting a corresponding wedge of the crested scion, sealing the union with grafting wax and securing it with twine for two to three weeks until the tissues fuse. The resulting Frankenstein-like composite — a wavy coral fan atop a smooth, leafy trunk — is one of the most recognisable and commercially successful grafted succulents in the world.
2. ‘White Ghost’ — The Nearly Achlorophyllous Cultivar
Euphorbia lactea ‘White Ghost’ (also marketed as ‘Grey Ghost’) is a chimeral variant that lacks most of the chlorophyll-bearing tissue of the green form, resulting in an almost entirely creamy-white or greyish plant with only small green patches representing reversions to the normal form. The effect is spectral and surreal — hence the name.
‘White Ghost’ grows more slowly than the green type and is more sensitive to direct sunlight (the reduced chlorophyll provides less protection against photodamage). It can be grown on its own roots under careful management but is often grafted for convenience. When ‘White Ghost’ tissue also undergoes fasciation, the result is the highly sought-after Euphorbia lactea ‘White Ghost Cristata’ — a crested, nearly white, coral-like form that commands premium collector prices.
New growth on ‘White Ghost’ plants often flushes pink or pinkish-red, adding a further dimension of colour to an already extraordinary plant.
3. Coloured Crested Forms — The Asian Grower Selection
Asian nurseries, particularly in Thailand and Indonesia, have selected a remarkable range of variously coloured crested forms of Euphorbia lactea. These include specimens with crests variegated in combinations of green, white, yellow, pink, violet, and magenta. The colour diversity arises from the interplay of chlorophyll distribution, anthocyanin expression, and the degree of chimaeral variegation in the crested tissue. These coloured forms are among the most visually spectacular cultivated succulents and are produced on an industrial scale for the international houseplant market.
CITES Status: A Targeted Exemption
The commercial significance of crested and mutant Euphorbia lactea forms led CITES to create a specific exemption in its Appendix II annotation. The current text states:
“Artificially propagated specimens of crested, fan-shaped or colour mutants of Euphorbia lactea*, when grafted on artificially propagated root stock of* Euphorbia neriifolia*, […] are not subject to the provisions of the Convention.”*
This exemption, which took effect on 12 January 2005, targets specifically the grafted coral cactus forms. The key conditions are threefold: the specimens must be artificially propagated, they must be crested, fan-shaped, or colour mutants (not the wild-type green form), and they must be grafted on Euphorbia neriifolia rootstock.
Trade data from CITES records confirm that Euphorbia lactea was among the top four most heavily traded succulent euphorbias globally, with over one million specimens reported in international trade between 1995 and 1999. The exemption was introduced specifically to reduce the enormous administrative burden of issuing CITES permits for plants that are entirely of nursery origin and pose no threat to wild populations.
Note that the typical green, non-crested form of Euphorbia lactea remains subject to CITES Appendix II provisions like all other succulent Euphorbia species.
Toxicology: Phorbol and the Latex
The white latex of Euphorbia lactea is particularly rich in phorbol-type diterpene esters — a class of compounds distinct from the euphol-type triterpenes found in species like Euphorbia ammak and Euphorbia tirucalli. Phorbol esters are potent co-carcinogens and tumour promoters, as well as severe skin and mucous membrane irritants.
In India, where the species has been cultivated for centuries, the latex has traditional medicinal applications. It has been used as a purgative, for the treatment of skin conditions, and in Ayurvedic preparations. However, the same latex that has ethnobotanical significance is also classified as a poison — the caustic, irritating alkaloids can cause severe contact dermatitis, keratoconjunctivitis (inflammation of the cornea and conjunctiva), and gastrointestinal damage upon ingestion.
⚠ Critical safety disclaimer — the remedy is also a poison. The latex of Euphorbia lactea is among the more dangerous of the commonly cultivated euphorbias due to its phorbol ester content. Contact with skin causes severe irritation and chemical burns that may blister. Contact with eyes can cause intense pain, corneal damage, and potential permanent vision impairment. Ingestion causes violent nausea, vomiting, and inflammation of the digestive tract. Phorbol esters are additionally classified as tumour-promoting agents — while they do not initiate cancer directly, they can promote tumour development in tissues already exposed to carcinogenic initiation. Under no circumstances should the latex or any part of the plant be consumed, applied to the skin, or used as a home remedy. All handling — especially pruning, cutting, grafting, and repotting — must be performed with gloves and protective eyewear. Any skin or eye contact should be rinsed immediately with large quantities of cold water.
Cultivation and Care
The Typical Green Form
The non-crested, non-variegated form of Euphorbia lactea is straightforward to grow. It prefers full sun, tolerates extreme heat, and requires well-draining mineral-rich substrate. Water thoroughly during the growing season when the soil has dried, and reduce watering drastically in winter. The plant is frost-tender (USDA zones 10a–11b) and must be protected below 2 °C. It grows moderately fast and can become a substantial landscape shrub in frost-free climates within a few years.
Crested and Grafted Forms (Coral Cactus)
Grafted Euphorbia lactea cristata requires slightly different management. The graft union is a vulnerability — avoid getting water directly on the junction, as trapped moisture can promote rot at the interface. Bright, indirect light is generally preferable to full direct sun, particularly for variegated and ‘White Ghost’ forms that are prone to sunburn. Keep the rootstock (Euphorbia neriifolia) adequately watered but not waterlogged — if the rootstock dies, the scion dies too.
Crested forms grow very slowly, and repotting is infrequent. Check the graft union periodically for signs of softening, darkening, or separation, which indicate graft failure or rot. If the scion separates or the rootstock deteriorates, the crested top can sometimes be re-grafted onto a fresh rootstock if caught early.
‘White Ghost’ on Its Own Roots
‘White Ghost’ can be grown successfully on its own roots, contrary to common belief. The key is to provide bright but filtered light (morning sun is ideal), avoid overwatering even more rigorously than with the green form, and accept a slower growth rate. The reduced chlorophyll means less photosynthetic capacity, so the plant is inherently less vigorous — but it is by no means impossible to grow ungrafted.
Propagation
The typical green form propagates readily from stem cuttings following the standard procedure: cut, rinse the latex, callus for one to two weeks, pot in dry mineral substrate. Rooting is best in warm conditions (spring/summer).
Crested and variegated forms are propagated almost exclusively by grafting. Cuttings of crested tissue rarely root successfully, and seed propagation is not viable because neither the fasciation nor the variegation is genetically stable through sexual reproduction. Grafting is a specialised skill, but the basic V-cut technique on Euphorbia neriifolia rootstock is well within the capabilities of an experienced succulent grower.
Pests and Problems
Euphorbia lactea is generally pest-resistant. Mealybugs may settle along the ribs or within the folds of crested tissue. Root and stem rot from excess moisture is the greatest threat, particularly at the graft union of grafted specimens. In crested, variegated forms, mites can occasionally establish in the tight crevices of the fan.
Sources
- Haworth, A.H. (1812). Synopsis Plantarum Succulentarum. [Original species description]
- Govaerts, R., Frodin, D.G. & Radcliffe-Smith, A. (2000). World Checklist and Bibliography of Euphorbiaceae (and Pandaceae) 1–4: 1–1622. The Board of Trustees of the Royal Botanic Gardens, Kew.
- Carter, S. & Eggli, U. (2003). The CITES Checklist of Succulent Euphorbia Taxa, 2nd edition. Federal Agency for Nature Conservation, Germany.
- Balakrishnan, N.P. & Chakrabarty, T. (2007). The family Euphorbiaceae in India. A synopsis of its profile, taxonomy and bibliography: 1–500. Bishen Singh Mahendra Pal Singh, Dehra Dun.
- Binojkumar, M.S. & Balakrishnan, N.P. (2010). The genus Euphorbia L. (Euphorbiaceae) in India. A taxonomic revision: 1–430. Bishen Singh Mahendra Pal Singh, Dehra Dun.
- Amtaghri, S. et al. (2022). Traditional uses, pharmacological, and phytochemical studies of Euphorbia: a review. Current Topics in Medicinal Chemistry 22(19): 1553–1576.
- Mavundza, E.J. et al. (2025). Pharmacological significance, medicinal use, and toxicity of extracted and isolated compounds from Euphorbia species found in Southern Africa: a review. Plants 14(3): 469.
Authority Pages
- POWO — Plants of the World Online, Royal Botanic Gardens, Kew: Euphorbia lactea Haw.
- CITES — Convention on International Trade in Endangered Species: Euphorbia lactea — Appendix II with explicit exemption for artificially propagated crested, fan-shaped, or colour mutants grafted on Euphorbia neriifolia
- GBIF — Global Biodiversity Information Facility: Euphorbia lactea Haw.
- IPNI — International Plant Names Index: Euphorbia lactea Haw.
- LLIFLE — Encyclopedia of Living Forms: Euphorbia lactea
- Wikispecies: Euphorbia lactea