Species
+

Euphorbia milii Des Moul.

Christ's-plant, Christ's-thorn, Christplant, Crown of Thorns (EN); Corona de Cristo

Climate known 56 photographs Cactus or succulent
Add one to my plants Sow seed

Every figure on this page is derived from public data by a stated rule and says its source; nothing here is written by a person or a model, except the Wikipedia passage, which is quoted and marked as such. How it is made.

Summary

Euphorbia milii, the crown-of-thorns, Christ plant or Christ's thorn, is a species of flowering plant in the spurge family, Euphorbiaceae, native to Madagascar. The epithet commemorates Baron Milius, once Governor of Réunion, who introduced the species to France in 1821.

Text from Wikipedia, “Euphorbia milii”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.

About the genus · Euphorbia

Euphorbia is a large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae.

Text from Wikipedia, “Euphorbia”, CC BY-SA 4.0, quoted as written.

Family
Euphorbiaceae
Described by
Des Moul.
Native to
Madagascar
Wild records
193 in range· 115 open

At a glance

Warmest month
27°C
Jan, mean day; nights 19 °C (CHELSA)
Rain
1488mm/yr
8 wet months · peak Jan 350 mm (CHELSA)
Light
25–43DLI
mol/m²/day, winter to summer, open sky (CHELSA shortwave)
In short condensed by rule from the cultivation cards · not written by a person
Grouped as a cactus or succulent by the genus Euphorbia, which is reliably one kind of plant (archetype table). Rain rule: a summer growing season, June to September in the northern hemisphere (December to March at the habitat, southern). Habitat rain 1488 mm a year, wettest January at 350 mm, driest June at 10 mm (habitat calendar, southern hemisphere). Open sky over the habitat: 25 to 43 mol/m²/day. Cold floor 7.3 °C (1st-percentile habitat night, NASA POWER).
Each sentence is one card's own one-line form, written by the same rule as the card (Its year, Rain, Light, Temperature); the note cannot say what a card does not. Months are given for the northern hemisphere (set your site in Settings to change this), and the habitat's own alongside. The cards · the figures.

Also known as Euphorbia bojeri Hook.; Euphorbia bojeri var. mucronulata Ram.Goyena; Euphorbia breonii Nois.; Euphorbia milii f. lutea Leandri; Euphorbia milii subsp. breonii (Nois.) Ursch & Leandri and 11 more.

Cultivation

Grouped as a cactus or succulent by the genus Euphorbia, which is reliably one kind of plant (archetype table). The table holds no figure for this group, which spans too much for one minimum; the cold floor is the habitat's alone, and no prose comes from the table.

Its year Rain rule: a summer growing season, June to September in the northern hemisphere (December to March at the habitat, southern).

This species’ habitat figures, and what two fixed rules read from them.

The rain rule reads a summer growing season: 70% of the year's rain (1132 mm of 1488 mm) falls in December to March, warmer than the year (wet-season mean 22.4 °C against a yearly mean of 20.1 °C). Months are the habitat's, southern hemisphere; shifted six months for a northern-hemisphere collection: June to September.

Read from the median year of CHELSA monthly rainfall and mean temperature across the envelope cells: the rain rule takes the smallest set of months carrying 70% of the rain and calls it winter when its mean is more than half a degree below the year's, summer when more than that above, and neither in between; the temperature rule, used only under 120 mm, names the cooler six months when they are at least a degree cooler than the other six. Months are shifted for the other hemisphere only where the temperature curve gives a season to reverse. A reading of the curves, not an observation of the plant.

Rain Habitat rain 1488 mm a year, wettest January at 350 mm, driest June at 10 mm (habitat calendar, southern hemisphere).

This species’ habitat figures, with their source.

1488 mm a year at the habitat, 1132 mm of it December to March. Wettest month January at 350 mm, driest June at 10 mm. Across the envelope cells the year's total runs 897 mm to 2461 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, southern hemisphere).

CHELSA monthly precipitation, median year across the envelope cells. The rain that falls where the species is recorded; nothing about how the plant takes water.

Light Open sky over the habitat: 25 to 43 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 25 to 43 mol/m²/day across the year (daily light integral, median year across the envelope cells, CHELSA; the lowest 10th-percentile month across the cells is 21, the highest 90th-percentile month 47).

CHELSA shortwave radiation at each envelope cell, a daily-mean flux taken to a daily total and converted at 2.07 mol of PAR per MJ. The sky over the habitat, measured; what reaches a plant under a rock, a shrub or a shade cloth is not.

Warmth and air Cold floor 7.3 °C (1st-percentile habitat night, NASA POWER).

This species’ habitat figures, with their source.

Temperature

Coldest: the 1st-percentile night over 44 years at the typical cell is 7.3 °C, the absolute minimum 4.5 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 37.6 °C. Monthly means: coldest night 11.3 °C in July (across the envelope cells 8.3 °C to 18.0 °C), warmest day 26.6 °C in January (median year across the envelope cells, CHELSA). Cold floor: 7.3 °C, which is the 1st-percentile night over 44 years at the typical cell (NASA POWER).

NASA POWER daily minima and maxima 1981–2024 at the typical cell, lapse-corrected to its elevation; CHELSA monthly means, median year across the envelope cells, CHELSA. The cold floor is the figure named in its sentence. Not a measured survival limit for any plant in a pot.

Humidity

Relative humidity at the habitat: 59 to 66% across the year (monthly means, median year across the envelope cells, CHELSA). A figure about the air, saying nothing about how the plant takes water.

CHELSA relative humidity, median year across the envelope cells.

The figures the cards read from are in Climate below, and where they came from in Natural habitat.

Climate across the habitat

Habitat climate through the yearMean day from 21 °C in Jul to 27 °C in Jan; mean night from 11 °C in Jul to 19 °C in Jan. The cold quarter, Jun to Aug, is the three months around the coldest night. 1488 mm of rain a year, most in Jan. The bands show the 10th to 90th percentile across 128 habitat cells. Over 44 years at the typical cell the absolute minimum was 4.5 °C and the 99th-percentile day 37.6 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.10°20°30°40°37.6° 99th-percentile day (undated)4.5° lowest night in 44 yrs (undated)°C · day and nightcold quarter0100200300400500mm rainDLI 25–43RH 59–66 %JanFebMarAprMayJunJulAugSepOctNovDec
day night rain 10th–90th percentile across 128 habitat cells cold quarter: the three months around the coldest night extremes over 44 years at the typical cell, marked at the edge: undated DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C27 / 24–3026 / 23–3026 / 23–3125 / 22–3024 / 20–2922 / 18–2721 / 17–2622 / 19–2824 / 21–3025 / 23–3126 / 24–3227 / 24–32
Night °C19 / 15–2419 / 15–2418 / 15–2316 / 13–2214 / 11–2112 / 9–1911 / 8–1812 / 9–1813 / 10–1915 / 12–2116 / 13–2218 / 15–23
Rain mm350 / 192–477292 / 168–467215 / 110–34469 / 38–22227 / 16–19410 / 2–12013 / 5–18312 / 3–10816 / 9–11571 / 31–127138 / 65–208275 / 148–370
DLI37 / 34–4336 / 33–4036 / 32–3932 / 28–3627 / 24–3225 / 21–3026 / 22–3132 / 27–3539 / 33–4142 / 37–4543 / 40–4741 / 38–45
RH %66 / 62–7066 / 62–7165 / 60–7064 / 58–6962 / 56–6862 / 54–6862 / 53–6861 / 52–6759 / 51–6559 / 53–6660 / 55–6664 / 59–68

Each figure is the median across the 128 grid cells holding the 185 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. Extremes and elevation were read at the typical cell 2257:4493 (-22.875, 44.675). Over 44 years there: absolute minimum 4.5 °C, 1st-percentile night 7.3 °C, 99th-percentile day 37.6 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Envelope: median and 10th–90th percentile of each month across the 128 distinct grid cells holding the 185 in-range records; extremes and elevation at the typical cell 2257:4493 (its coldest month's mean night nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell -23.00_44.375, lapse-corrected +318 m at 6.5 °C/km. Elevation: ETOPO 2022, 764 m (cell mean).

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing: the climate was read across every in-range record's cell, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeMadagascar· introduced: Canary Is., Gambia, The, Comoros, China South-Central, Hainan, China North-Central, China Southeast, Taiwan, Assam, Bangladesh, India, Myanmar, Mexico Central, Cayman Is., Cuba, Dominican Republic, Haiti, Leeward Is. AB Ant, Puerto Rico, Trinidad-Tobago, Bolivia
Kew's description“semisucculent subshrub or shrub” · “desert or dry shrubland”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Map marker-18.942, 47.297 · in the densest population, 133 records (69% of those in range)
Evidence usedThe map marker and the climate envelope rest on all 193 georeferenced records inside the native range; the map shows only the 115 openly licensed ones, which alone would put the marker 162 km away. 1504 records outside the range (gardens, roadsides, misidentifications) ignored. 8 in-range records are placed to worse than 10 km and stay on the map but off the climate.
The map markerthe map marker: the openly licensed record nearest the middle of the densest 1° population inside the densest 2° block of the 193 in-range records; it decides nothing.

Photographs

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Photographs: (c) Louis Aureglia, some rights reserved (CC BY) (7); (c) Micha Baum, some rights reserved (CC BY-SA).

Photographs: iNaturalist did not answer when this page was built; what is shown came from the sources that did.

Papers naming this species

Works whose title or abstract names Euphorbia milii, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Structural and optical properties of pure and copper doped zinc oxide nanoparticles
Muhammad Sajjad, I. Ullah, Mohammad Iqbal Khan, Jamshid Khan (2018) · Results in Physics
Toxicity of Euphorbia milii Latex and Niclosamide to Snails and Nontarget Aquatic Species
Eduardo Cyrino Oliveira-Filho, Francisco José Roma Paumgartten (2000) · Ecotoxicology and Environmental Safety
Highly stable glycosylated serine protease from the medicinal plant Euphorbia milii
Subhash Chandra Yadav, Monu Pande, Medicherla V. Jagannadham (2006) · Phytochemistry
Comparative toxicity of Euphorbia milii latex and synthetic molluscicides to Biomphalaria glabrata embryos
Eduardo Cyrino Oliveira-Filho, Bárbara Rodrigues Geraldino, Deise Riba Coelho, Rosângela R. De-Carvalho (2010) · Chemosphere
Antinociceptive, muscle relaxant and sedative activities of gold nanoparticles generated by methanolic extract of Euphorbia milii
Nazar Ul Islam, Ibrahim Khan, Abdur Rauf, Naveed Muhammad (2015) · BMC Complementary and Alternative Medicine
Taxonomy and Medicinal Uses of Euphorbiaceae (Spurge) Family of Rajshahi, Bangladesh
A.H.M. Mahbubur Rahman, Momota Akter (2013) · Research in Plant Sciences
Purification and biochemical characterization of Eumiliin from Euphorbia milii var. hislopii latex
Kelly Cortes Fonseca, Nadia Cristina Gomes de Morais, Mayara Ribeiro de Queiroz, M.C. Silva (2010) · Phytochemistry
Molluscicidal milliamines from Euphorbia milii var. hislopii
Carlos Leomar Zani, Andrew Marston, Matthias Hamburger, Kurt Hostettmann (1993) · Phytochemistry
Green synthesis of stable silver nanoparticles using Euphorbia milii latex
Ricardo Almeida de Matos, Thiago da Silva Cordeiro, Ricardo Elgul Samad, Nilson Dias Vieira (2011) · Colloids and Surfaces A Physicochemical and Engineering Aspects

Similar habitat climate the 6 species whose habitat climate is nearest this one's: mean day and night, month by month, and rain on a log scale, in calendar order, so a habitat with the same seasons six months out is far, not near. Nothing else counts: not range, not family.

Other Euphorbia 29 in the reference

History & registers

Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)
gbif.synonyms answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)
gbif.vernacular answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)
wcvp.distribution answered
gbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zam
climate answered
wikidata answeredcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
wikipedia answeredcarried from build of 2026-09-19; this build: skipped
inat.taxon not asked
inat.photos.wild answeredcarried from build of 2026-09-19; this build: skipped
inat.photos.cultivated nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
commons nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
gbif.media answered
openalex answeredcarried from build of 2026-09-19; this build: skipped

Every upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 120 datasets via GBIF.org; each carries its own licence.