Species
+

Allium triquetrum L.

Angled Onion, Onion weed, Three-Cornered Garlic, Three-Cornered Leek

Climate known 69 photographs Bulb, tuber or caudex
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

Allium triquetrum is a bulbous flowering plant in the genus Allium native to the Mediterranean basin. It is known in English as three-cornered leek or three-cornered garlic, in Australia as angled onion, and in New Zealand as onion weed. Both the English name and the specific epithet triquetrum refer to the three-cornered shape of the flower stalks.

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

About the genus · Allium

Allium is a large genus of monocotyledonous flowering plants with 1112 accepted species, making Allium the largest genus in the family Amaryllidaceae and among the largest plant genera in the world. Many of the species are edible, and some have a long history of cultivation and human consumption such as the onion, garlic, scallions, shallots, leeks, and chives.

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

Family
Amaryllidaceae
Described by
L.
Native to
Baleares, Corse, France +8
Wild records
818 in range· 518 open

At a glance

Warmest month
22°C
Aug, mean day; nights 16 °C (CHELSA)
Rain
938mm/yr
12 wet months · peak Dec 116 mm (CHELSA)
Light
7–41DLI
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 bulb, tuber or caudex by Amaryllidaceae, which is usually but not always one kind of plant (archetype table). Rain rule: no season, 70% of the rain takes 8 months (September to April in the northern hemisphere). Habitat rain 938 mm a year, wettest December at 116 mm, driest July at 47 mm (habitat calendar, northern hemisphere). Open sky over the habitat: 7 to 41 mol/m²/day. Cold floor 3.8 °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 Allium medium G.Don; Allium opizii Wolfner; Allium triquetrum f. normale Maire & Weiller; Allium triquetrum subsp. bulbiferum Batt. & Trab.; Allium triquetrum var. bulbiferum Batt. & Trab. and 4 more.

Cultivation

Grouped as a bulb, tuber or caudex by Amaryllidaceae, which is usually but not always 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: no season, 70% of the rain takes 8 months (September to April in the northern hemisphere).

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

The rain rule reads no season: 70% of the year's rain (727 mm of 938 mm) takes 8 months, September to April. Mean temperature moves 11.5 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: March to October.

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 938 mm a year, wettest December at 116 mm, driest July at 47 mm (habitat calendar, northern hemisphere).

This species’ habitat figures, with their source.

938 mm a year at the habitat, 727 mm of it September to April. Wettest month December at 116 mm, driest July at 47 mm. Across the envelope cells the year's total runs 668 mm to 1335 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, northern 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: 7 to 41 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 7 to 41 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 5, 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 3.8 °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 3.8 °C, the absolute minimum -5.6 °C, 11 frost nights in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 29.8 °C. Monthly means: coldest night 5.1 °C in February (across the envelope cells 2.4 °C to 8.6 °C), warmest day 22.1 °C in August (median year across the envelope cells, CHELSA). Cold floor: 3.8 °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: 62 to 64% 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 9 °C in Feb to 22 °C in Aug; mean night from 5 °C in Feb to 16 °C in Aug. The cold quarter, Jan to Mar, is the three months around the coldest night. 938 mm of rain a year, most in Dec. The bands show the 10th to 90th percentile across 626 habitat cells. Over 44 years at the typical cell the absolute minimum was -5.6 °C and the 99th-percentile day 29.8 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.-10°10°20°30°40°frost29.8° 99th-percentile day (undated)-5.6° lowest night in 44 yrs (undated)°C · day and nightcold quarter050100150200mm rainDLI 7–41RH 62–64 %JanFebMarAprMayJunJulAugSepOctNovDec
day night rain 10th–90th percentile across 626 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 °C10 / 8–129 / 8–1311 / 9–1514 / 11–1717 / 14–2020 / 16–2422 / 18–2822 / 18–2820 / 17–2416 / 14–2012 / 11–1610 / 8–13
Night °C6 / 3–95 / 2–97 / 4–108 / 5–1211 / 9–1514 / 11–1916 / 13–2216 / 14–2214 / 12–1912 / 9–169 / 6–136 / 3–10
Rain mm96 / 59–14375 / 50–11272 / 49–10771 / 53–11667 / 42–9249 / 22–7047 / 9–7548 / 20–7774 / 55–103110 / 85–162113 / 83–178116 / 77–171
DLI8 / 6–1413 / 11–2021 / 18–2931 / 28–3637 / 34–4241 / 36–4739 / 34–4733 / 29–4125 / 21–3215 / 12–229 / 7–157 / 5–12
RH %64 / 60–6763 / 59–6562 / 59–6562 / 59–6462 / 58–6562 / 56–6563 / 55–6663 / 56–6663 / 59–6564 / 61–6664 / 60–6764 / 60–68

Each figure is the median across the 626 grid cells holding the 813 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 935:3730 (43.225, 6.525). Over 44 years there: absolute minimum -5.6 °C, 1st-percentile night 3.8 °C, 99th-percentile day 29.8 °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 626 distinct grid cells holding the 813 in-range records; extremes and elevation at the typical cell 935:3730 (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 43.00_6.250, lapse-corrected +22 m at 6.5 °C/km. Elevation: ETOPO 2022, 111 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.
NativeBaleares, Corse, France, Portugal, Sardegna, Spain, Italy, Sicilia, Algeria, Morocco, Tunisia· introduced: Great Britain, Ireland, Germany, Turkey-in-Europe, Azores, Canary Is., Madeira, Cape Provinces, New South Wales, South Australia, Tasmania, Victoria, Western Australia, New Zealand North, New Zealand South, Oregon, California, Argentina Northeast, Falkland Is.
Kew's description“bulbous geophyte” · “subtropical”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Map marker48.519, -3.861 · in the densest population, 428 records (52% of those in range)
Evidence usedThe map marker and the climate envelope rest on all 818 georeferenced records inside the native range; the map shows only the 518 openly licensed ones, which alone would put the marker 119 km away. 803 records outside the range (gardens, roadsides, misidentifications) ignored. 5 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 818 in-range records; it decides nothing.

Photographs

Allium triquetrumAllium triquetrumAllium triquetrumAllium triquetrumAllium triquetrumAllium triquetrumAllium triquetrumAllium triquetrum

Photographs: no rights reserved · CC0 (2); (c) Ian Rainbow, some rights reserved (CC BY); (c) Ian Webb, some rights reserved (CC BY) (3); (c) zebedeugalinha, some rights reserved (CC BY) (2).

Photographs: iNaturalist and Wikimedia Commons 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 Allium triquetrum, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Wild food plants of popular use in Sicily
Francesca Lentini, Francesca Venza (2007) · Journal of Ethnobiology and Ethnomedicine
Water status and associated processes mark critical stages in pollen development and functioning
Nurit Firon, Massimo Nepi, Ettore Pacini (2012) · Annals of Botany
Role of Saponins in Plant Defense Against Specialist Herbivores
Mubasher Hussain, Biswojit Debnath, Muhammad Qasim, Bamisope Steve Bamisile (2019) · Molecules
Pollen Developmental Arrest: Maintaining Pollen Fertility in a World With a Changing Climate
Ettore Pacini, Rudy Dolferus (2019) · Frontiers in Plant Science
Natural Polymers-Based Materials: A Contribution to a Greener Future
Ana C. Q. Silva, Armando J. D. Silvestre, Carla Vilela, Carmen S. R. Freire (2021) · Molecules
Flora of Macaronesia. Checklist of vascular plants. 4. revised edition
Aslak Kappel Hansen, P. Sunding (1993) · Sommerfeltia
Steroidal saponins from the genus Allium
Danuta Sobolewska, Klaudia Michalska, Irma Podolak, Karolina Grabowska (2014) · Phytochemistry Reviews
Plants and traditional knowledge: An ethnobotanical investigation on Monte Ortobene (Nuoro, Sardinia)
Maria Adele Signorini, Maddalena Piredda, Piero Bruschi (2009) · Journal of Ethnobiology and Ethnomedicine
Underrated aspects of a true Mediterranean diet: understanding traditional features for worldwide application of a “Planeterranean” diet
Justyna Godos, Francesca Scazzina, Corrado Paternò Castello, Francesca Giampieri (2024) · Journal of Translational Medicine
Allium Flavonols: Health Benefits, Molecular Targets, and Bioavailability
Damini Kothari, Woo‐Do Lee, Soo‐Ki Kim (2020) · Antioxidants
Endemic and Emerging Pathogens Threatening Cork Oak Trees: Management Options for Conserving a Unique Forest Ecosystem
Salvatore Moricca, Benedetto Teodoro Linaldeddu, Beatrice Ginetti, Bruno Scanu (2016) · Plant Disease

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 Allium 12 in the reference

History & registers

Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.synonyms answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.vernacular answeredcarried from build of 2026-09-20 (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 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
wikipedia answeredcarried from build of 2026-09-20; this build: skipped
inat.taxon not askedcarried from build of 2026-09-20 (rederive)
inat.photos.wild answeredcarried from build of 2026-09-20; this build: skipped
inat.photos.cultivated nothing to reportcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
commons not askedcarried from build of 2026-09-20 (rederive); that build: carried 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 2026-09-20; 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 86 datasets via GBIF.org; each carries its own licence.