Threecorner Leek Allium triquetrum
Threecorner Leek is an introduced perennial herb, found in the lower 48 states. It grows to 1.3 ft and blooms Mar – May.
More about this plant
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. Wikipedia →
Threecorner Leek is flagged invasive in the U.S. These natives fill a similar niche — same growth habit, bloom season, height, and region — so you keep the look and feed local wildlife instead of spreading a problem.
Part of why it adapts so well: Threecorner Leek is a polyploid complex — multiple chromosome races are on record (2n = 16, 18). Spare genome copies give a plant extra raw material to evolve fast, and polyploidy is a documented correlate of successful plant invasions (te Beest et al. 2012). A labelled association from open cytology (ChromoDB), not a prediction for your specific site.
Growing & care
USDA PLANTS · TRY- Hardiness
- ≥ zone 9 derived from its U.S. range
- Height
- 1.3 ft
- Lifespan
- Perennial
- Foliage
- Broadleaf
- Flower colour
- White AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
Wildlife & pollinators
How pollinator value is scored →❧ Caterpillar hosts ~21 caterpillar species
Allium supports ~21 caterpillar species.
Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a moderate genus.
Recorded feeding on Allium in North America, including:
+ 8 more species → ↑ show fewer
✦ Bees 22 bee visitors
22 native & managed bee species are documented visiting Threecorner Leek — the 12 most-recorded:
Wildlife & visitors 1 bird · 11 nectaring
Open records of who else uses Threecorner Leek — a generalist food-web signal, kept separate from the keystone Ecological Value.
Recorded eaten by 1 bird species (fruit, seed, browse):
11 adult butterfly & moth species are recorded nectaring at its flowers — the most-recorded:
Related plants
More Allium →
How we know this (4) Methods & honest limits
We read each species’ measured specific leaf area (leaf area per unit dry weight) from the Global Spectrum dataset and band it: thin & fast (high SLA), medium, or thick & tough (low SLA). The global median is about 10 mm²/mg.
Honest limits: A species-mean from pooled measurements — individual plants vary with light and site. A broad strategy signal, not a precise per-plant figure.
A recorded categorical fact: each species is tagged C3 (standard), C4 (heat/water-efficient) or CAM (succulent, night-time CO₂ uptake) — or a facultative combination. We only show a trait card for the noteworthy C4/CAM cases; C3 is the unremarkable majority, kept in the data but not surfaced as a card.
We take the plant’s U.S. county range and look up each county’s long-term climate, then summarise: native rainfall = the median annual rainfall across its counties; heat tolerance = the warm end (90th percentile) of average temperature across its range (mirroring how our cold-hardiness floor uses an extreme). Counties + medians blunt the roadside/observer bias that makes point-level climate unreliable. Needs at least five placeable counties.
Honest limits: A realized, sampling-biased niche (where it has been recorded, not its physiological optimum), and county climate is coarse — large Western counties span deserts and mountains. Derived guide, never a measured fact.
McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.
Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.
Sources for this entry (26) Open & cited
Cite this page Open data, please attribute
PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).
Loading…
BibTeX
Loading…