Conditional — Some Areas
rosemary (zones 8-10) reaches only part of Utah (4a-9a): zones 8-9 are in range, so where you are in the state decides it.
Rosemary in Utah — the short answer
Rosemary in Utah: hardy in zones 8–10, full sun, against a state median of ~175 frost-free days.
- Plant zones
- 8-10
- 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
- 90 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 rosemary 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 rosemary 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 Rosemary Stands in Utah
Rosemary is rated for zones 8–10 — a cold floor USDA puts at 10 to 20°F. No Utah county sits inside it, so in open ground this is a grown-under-cover plant here rather than a bed plant — which is a statement about Utah winters, not about rosemary.
Below the zone 8 floor
29 counties
- Rich County · zone 4b
- Daggett County · zone 5b
- Iron County · zone 5b
3 of 29 shown
Winter cold is the limit here — the same plant works in a container that comes under cover.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.
Zone Comparison
Rosemary Needs
- USDA Zones: 8-10
- Frost-Free Days: 120+
- Sun: Full Sun
- Mature size: 4 ft tall
- Picking window: ~120 days of harvest
- Drought tolerance: High
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 8-10)
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 Rosemary 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.
When to start the seed
Those dates are when rosemary goes out, not when it starts. It is sown under cover about 10 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.
Winter standing
Rosemary overwinters from USDA zone 8 and warmer (NC State Extension Gardener Plant Toolbox; Missouri Botanical Garden Plant Finder), and Utah runs as cold as zone 4, so it does not survive winter in the ground here. It is a woody plant rather than a crop you resow each spring, so neither a fall establishment date nor a harvest countdown describes it in Utah — which is why this page gives neither. What it needs here is a way through winter, not a planting date.
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 rosemary survives winter in part of Utah, not across all of it. Whether the season is long enough — and warm enough — is a different question.
Frost-free days
Rosemary 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
Rosemary needs ~2500 GDD (base 50°F) to ripen. The state median runs ~2690 GDD (from PRISM 1991-2020 climate normals), so Utah sits right at the threshold — pay attention to siting and microclimate.
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
Rosemary tolerates a wide pH range (pH 4.2-8.3) — 4.1 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 5 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 rosemary 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 rosemary 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.
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 Rosemary 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 rosemary — is covered on the Utah growing guide.
Timing shifts within Utah
Rosemary 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 rosemary 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"). Rosemary'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
Rosemary draws honeybees and native bees (high value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, rosemary 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. Deer pressure is meaningful across much of Utah; rosemary is listed as deer-resistant (USDA PLANTS Database), which makes it a safer pick for unfenced sites. Our deer & wildlife guide carries the full deer-resistant list and how to protect the rest.
Utah Cooperative Extension
For Utah-specific cultivar recommendations, planting calendars, and pest pressure for rosemary, the canonical source is Utah State University Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Common Questions About Growing Rosemary in Utah
When can I plant Rosemary 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). Rosemary overwinters only from USDA zone 8 and warmer, and Utah runs as cold as zone 4, so it does not survive winter in the ground here — the question for Utah growers is how to carry it through winter under cover, not which week to plant it.
What hardiness zone is Rosemary grown in across Utah?
Utah spans USDA hardiness zones 4a-9a (USDA ARS PHZM 2023). Rosemary carries a range of zones 8-10, 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). Rosemary needs 120+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
How should I amend the soil for Rosemary in Utah?
Rosemary tolerates pH 4.2-8.3 and well (dry spells) drainage (FAO ECOCROP). That is a 4.1-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 Rosemary actually grow on my specific land in Utah?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores rosemary 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 rosemary against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Utah rosemary 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 rosemary average
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