Yes — Strong Match
leek (zones 2-11) covers every zone Utah contains (4a-9a), so hardiness is not what limits it anywhere in the state.
Leek in Utah — the short answer
Leek in Utah: hardy in zones 2–11, full sun, against a state median of ~175 frost-free days.
- Plant zones
- 2-11
- Manual horticultural correction (source not retained); NC State Extension and Missouri Botanical Garden, with the remaining rows from other published sources or Growable Ground compilation
- Utah zones
- 4a-9a
- USDA PHZM 2023
- Frost window
- Apr 12 - May 6 – Oct 8 - Oct 27
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 98 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
- Days to maturity
- 100 days
- Growable Ground Plant Database
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.
Your yard isn't the whole zone.
Utah spans zones 4a-9a, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score leek against your parcel's actual hardiness, soil, and sun.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
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Utah is not one climate
Utah’s winter-low ladder runs across 29 counties, from zone 4.5 in Rich County to zone 7.5 in Washington County. That is 30°F between the two counties’ average coldest night — the difference between leek overwintering in the ground and coming under cover.
The middle half of 29 counties runs 6–7 zones, with a median of 6.5 zones — a 3-zone span end to end.
Measured across 29 Utah counties. USDA PHZM 2023, per county. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.
Where in Utah Fits Best
Even within Utah's zones 4a-9a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for leek (USDA PHZM 2023):
Zone Comparison
Leek Needs
- USDA Zones: 2-11
- Frost-Free Days: 120+
- Sun: Full Sun
- Mature size: 2.5 ft tall
- Picking window: ~60 days of harvest
- Drought tolerance: Low
Utah Has
- USDA Zones: 4a-9a
- Last Hard Freeze (28°F): Apr 12 - May 6
- First Hard Freeze (28°F): Oct 8 - Oct 27
- Annual Rainfall: 5-20 inches
- Common Soils: Sandy loam, Alkaline clay, Desert sand
Plant Zone Range (zones 2-11)
Preferred Soil pH
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant Leek in Utah
The frost window
Across Utah, the last spring hard freeze (28°F) clears between Apr 12 and May 6, and the first fall hard freeze lands between Oct 8 and Oct 27 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 155-day window you can count on — up to 198 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Frost hardiness
Leek takes cold down to about 23°F before a freeze kills it (FAO ECOCROP), so you can plant on the early side of Utah's window — even a few weeks before the final hard freeze. That is the point where cold damages growing tissue, not a winter-survival floor — an established perennial comes through far colder while dormant, which is what its hardiness zone tells you.
When to start the seed
Those dates are when leek goes out, not when it starts. It is sown under cover about 8 weeks ahead, so counting back from Utah's late-side last freeze of May 6 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.
Grown as an annual here
Leek is a true perennial in its home range — it overwinters from USDA zone 5 and warmer (NC State Extension Gardener Plant Toolbox; Missouri Botanical Garden Plant Finder) — but Utah runs as cold as zone 4, so it is killed back each winter and replanted each spring. Treat it on the season schedule above, not as a permanent planting: there is no fall establishment window for it here.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Growing Season Fit
The zone check says leek survives winter here. Whether the season is long enough — and warm enough — is a different question.
Frost-free days
Leek wants 120+ frost-free days; a typical Utah site sees ~175 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves a workable window — start indoors to bank time.
Growing degree days
Leek needs ~1500 GDD (base 50°F) to ripen. The state median runs ~2690 GDD (from PRISM 1991-2020 climate normals), so Utah's typical season clears that easily.
GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.
Soil + Drainage Fit
Leek tolerates a wide pH range (pH 4.5-7.5) — 3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Utah. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 6 and 6.5 — worth knowing before you decide whether a Utah soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Utah site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Utah soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
Before you plant leek for food
Anything you grow to eat takes up what is in the ground it grows in, so what is on record near you is worth knowing before leek goes in. What follows is Utah’s documented federal record at state scale — a screening signal, not a soil test, and not a statement about any one lot.
Safe to Grow Here?
What the federal record shows across Utah — and how to grow with it.
We checked the federal record across Utah — 17,478 documented sites across 8 of the 9 source types we track.
The most significant on record: 202 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Utah carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources Checked
across Utah
Severity Distribution
across Utah
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Utah, Mining runs higher than the national average — 3,654 sites across Utah. That's not a problem with your land — it's information about it.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What Else to Consider for Leek in Utah
Zone compatibility tells you about winter cold survival — but Utah growers also need to think about:
Very low rainfall — irrigation essential
Alkaline soils (pH 7.5-8.5) limit many species
High altitude frost risk in mountain valleys
What to actually do about these — and the constraints that apply to every Utah grower, not just leek — is covered on the Utah growing guide.
Timing shifts within Utah
Leek needs about 120 days of frost-free season to complete its cycle. 26 of Utah’s 29 counties give it that outright. The tightest that does is Sevier County at 136 frost-free days — 16 to spare. Below that line you are transplanting or extending the season, not direct-sowing.
Across Utah’s 29 counties the frost-free season runs from 98 days in Summit County to 237 days in Washington County — a spread of 139 days, which is why a single statewide planting date misleads. The median Utah county sees 175 frost-free days, leaving leek about 55 days of slack on a typical parcel — room for a second sowing where the season runs long.
County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Leek's 120-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.
Pollinator + Wildlife Value
Leek draws honeybees, native bees, and butterflies (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, leek can only work that bloom inside Utah's frost window — roughly 175 days, opening after the last 28°F freeze (Apr 12 - May 6) and closing at the first (Oct 8 - Oct 27), per NOAA Regional Climate Centers ACIS, 1991-2020.
Utah Cooperative Extension
For Utah-specific cultivar recommendations, planting calendars, and pest pressure for leek, the canonical source is Utah State University Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Leek native to Utah?
No — the USDA PLANTS Database lists Leek as introduced rather than native in the Lower 48, so it is not part of Utah's native flora. It grows here as a garden plant; pairing it with a few Utah natives keeps local pollinators fed too.
Looking for plants that belong here? The Utah growing guide lists USDA-documented natives for the state.
Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.
Common Questions About Growing Leek in Utah
When can I plant Leek in Utah?
Utah's last spring hard freeze (28°F) clears between Apr 12 and May 6, and the first fall hard freeze lands between Oct 8 and Oct 27 (NOAA Regional Climate Centers ACIS, 1991-2020). Leek overwinters only from USDA zone 5 and warmer, and Utah runs as cold as zone 4, so it is grown as an annual here — plant it after the last hard freeze, two to three weeks later for tender stock, and expect to replant next spring rather than establishing it for the long term.
What hardiness zone is Leek grown in across Utah?
Utah spans USDA hardiness zones 4a-9a (USDA ARS PHZM 2023). Leek carries a range of zones 2-11, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Utah site have?
A typical Utah site sees ~175 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Leek needs 120+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Leek native to Utah?
No — the USDA PLANTS Database lists Leek as introduced rather than native in the Lower 48, so it is not part of Utah's native flora. It grows here as a garden plant; pairing it with a few Utah natives keeps local pollinators fed too.
How should I amend the soil for Leek in Utah?
Leek tolerates pH 4.5-7.5 and well (dry spells) drainage (FAO ECOCROP). That is a 3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Utah site — amend for drainage and organic matter first.
Will Leek actually grow on my specific land in Utah?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores leek against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Utah
State-level data is a sketch. Your Growable Ground report scores leek against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Utah leek averages can't show:
We read public map data around Utah — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Utah leek average
Explore More
Growing guides for leek
Explore Utah county by county
Utah carries 29 counties with their own USDA zone — a sample of the growing pages for leek there:
Where else leek grows
Leek's zone band crosses state lines — these are the states closest to Utah in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.
More to grow in Utah
Utah has a growing page for 1,038 plants — a rotating sample of the rest of the shelf.
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