Conditional — Some Areas
rosemary (zones 8-10) reaches only part of Alaska (1a-9a): zones 8-9 are in range, so where you are in the state decides it.
Rosemary in Alaska — the short answer
Rosemary in Alaska: hardy in zones 8–10, full sun.
- Plant zones
- 8-10
- NC State Extension Gardener Plant Toolbox
- Alaska zones
- 1a-9a
- USDA PHZM 2023
- Frost window
- Apr 16 - May 15 – Sep 24 - Oct 29
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 85 days
- NOAA Regional Climate Centers ACIS station record, 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.
Alaska spans zones 1a-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.
No card required · your parcel report in seconds — read in full free for your first 14 days
Alaska is not one climate
Alaska’s winter-low ladder runs across 30 counties, from zone 1 in Yukon-Koyukuk County to zone 7.5 in Chugach County. That is 65°F between the two counties’ average coldest night — the difference between rosemary overwintering in the ground and coming under cover.
The middle half of 30 counties runs 2.5–5 zones, with a median of 4 zones — a 6.5-zone span end to end.
Measured across 30 Alaska 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 Alaska
Rosemary is rated for zones 8–10 — a cold floor USDA puts at 10 to 20°F. No Alaska 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 Alaska winters, not about rosemary.
Below the zone 8 floor
30 counties
- Yukon-Koyukuk County · zone 1a-4a
- North Slope County · zone 1b-4a
- Northwest Arctic County · zone 1b-4a
3 of 30 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
- Sun: Full Sun
- Mature size: 4 ft tallWe haven't confirmed this against a published source yet.
- Picking window: ~120 days of harvestWe haven't confirmed this against a published source yet.
- Drought tolerance: HighWe haven't confirmed this against a published source yet.
Alaska Has
- USDA Zones: 1a-9a
- Last Hard Freeze (28°F): Apr 16 - May 15
- First Hard Freeze (28°F): Sep 24 - Oct 29
- Annual Rainfall: 10-160 inches
- Common Soils: Permafrost, Glacial silt, Volcanic ash
Plant Zone Range (zones 8-10)
Preferred Soil pH
We haven't confirmed this against a published source yet.
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 Alaska
The frost window
Across Alaska, the last spring hard freeze (28°F) clears between Apr 16 and May 15, and the first fall hard freeze lands between Sep 24 and Oct 29 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 132-day window you can count on — up to 196 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 Alaska's late-side last freeze of May 15 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), and Alaska runs as cold as zone 1, 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 Alaska — 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.
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 Alaska. 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 Alaska soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Alaska site is heavier clay or sits in a low spot, a raised bed lifts the roots above wet ground, or work in compost. pH range, preferred pH and drainage need: We haven't confirmed this against a published source yet.
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. Alaska 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 Alaska’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 Alaska — and how to grow with it.
We checked the federal record across Alaska — 9,096 documented sites across 6 of the 8 source types we track.
The most significant on record: 281 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Alaska 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 of imported, lab-tested soil grow well almost anywhere in the meantime.
Sources Checked
across Alaska
Severity Distribution
across Alaska
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Alaska, two things run higher than the national average across Alaska — Mining (5,812 sites) and Superfund (281 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Sources: EPA, USGS — 950K documented sites tracked nationwide across 8 federal source types.
What Else to Consider for Rosemary in Alaska
Zone compatibility tells you about winter cold survival — but Alaska growers also need to think about:
Extremely short growing season (70-110 frost-free days)
Permafrost prevents deep root growth in many areas
Limited soil development in glacial terrain
What to actually do about these — and the constraints that apply to every Alaska grower, not just rosemary — is covered on the Alaska growing guide.
Where in Alaska Rosemary Is Zone-Hardy
Rosemary is rated for USDA zones 8–10. No single Alaska county falls inside it: 22 are colder than the plant’s zone 8 floor and 0 are milder than its zone 10 ceiling. A band this narrow straddles the state rather than sitting inside it.
Across those 30 counties Alaska’s winter-low ladder runs from zone 1a-4a in Yukon-Koyukuk County to zone 7b in Chugach County — 6.5 USDA zones of spread, which is 65°F between the two counties’ average coldest night of the year. None of that range reaches the band rosemary needs, so here the statewide answer really is the answer.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. Rosemary’s zone 8–10 band: NC State Extension Gardener Plant Toolbox. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Pollinator + Wildlife Value
Rosemary draws honeybees and native bees (high value). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, rosemary can only work that bloom inside Alaska's frost window — roughly 147 days, opening after the last 28°F freeze (Apr 16 - May 15) and closing at the first (Sep 24 - Oct 29), per NOAA Regional Climate Centers ACIS station record, 1991-2020. Deer pressure is meaningful across much of Alaska; rosemary is listed as deer-resistant (NC State Extension Gardener Plant Toolbox), 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. Pollinator value: We haven't confirmed this against a published source yet.
Good to Know Before You Plant Rosemary
Listed as non-toxic to dogs and cats by a source we can't cite. We haven't confirmed this against a published source yet.
Alaska Cooperative Extension
For Alaska-specific cultivar recommendations, planting calendars, and pest pressure for rosemary, the canonical source is UAF Cooperative Extension Service. Their fact sheets carry the local trial data we can't generalize across 50 states.
Common Questions About Growing Rosemary in Alaska
When can I plant Rosemary in Alaska?
Alaska's last spring hard freeze (28°F) clears between Apr 16 and May 15, and the first fall hard freeze lands between Sep 24 and Oct 29 (NOAA Regional Climate Centers ACIS, 1991-2020). Rosemary overwinters only from USDA zone 8 and warmer, and Alaska runs as cold as zone 1, so it does not survive winter in the ground here — the question for Alaska growers is how to carry it through winter under cover, not which week to plant it.
What hardiness zone is Rosemary grown in across Alaska?
Alaska spans USDA hardiness zones 1a-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 Alaska site have?
A typical Alaska site sees ~147 frost-free days per year (derived from NOAA Regional Climate Centers ACIS station record, 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 Alaska?
Rosemary tolerates pH 4.2-8.3 and well (dry spells) drainage. We haven't confirmed this against a published source yet. That is a 4.1-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Alaska site — amend for drainage and organic matter first.
Will Rosemary actually grow on my specific land in Alaska?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores rosemary against your address's mapped soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Alaska
State-level data is a sketch. Your Growable Ground report scores rosemary against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.
Three things about your lot that Alaska rosemary averages can't show:
We read public map data around Alaska — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Alaska rosemary average
Explore More
Growing guides for rosemary
Explore Alaska county by county
Alaska carries 30 counties with their own USDA zone — a sample of the growing pages for rosemary there:
Where else rosemary grows
Rosemary's zone band crosses state lines — these are the states closest to Alaska 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 Alaska
Alaska has a growing page for 1,011 plants — a rotating sample of the rest of the shelf.
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