mache (Valerianella locusta), photographi

Can I Grow Mache in Alaska?

USDA Zones 1a-9a · Plant zone range Data pending

Yes — Strong Match

mache is grown as an annual, so season length decides it here, not a winter zone — and Alaska's typical season runs ~147 frost-free days against the ~45 mache needs.

Sow by about Aug 10

Mache is grown as an annual, so what decides it here is season length, not a winter zone. It needs about 45 frost-free days and a typical Alaska season runs ~147 frost-free days, leaving 102 days of slack. That is room to sow as late as about Aug 10 and still finish before the usual first freeze (Sep 29), or to run a second succession.

Want more weeks at either end of that window? How to buy the weeks →

45 frost-free days required against Alaska’s ~147-day season. NOAA Regional Climate Centers ACIS 1991-2020 (28°F killing freeze), state median across counties, via stateClimateData.ts.

Mache in Alaska — the short answer

Mache in Alaska: full sun, against a state median of ~147 frost-free days.

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
50 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.

Score your parcel · free

Your yard isn't the whole zone.

Mache is grown as an annual, so your winter zone isn't the deciding factor — your frost-free window is. A typical Alaska site runs ~147 frost-free days, but that is a state median, not your yard: slope, trees, and low spots move the last-frost date across a single parcel. Enter your address and we'll score mache against your land's actual frost dates, sun, and soil.

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

No card required · your full report in seconds

mache (Valerianella locusta), photograph
Photo: Jochen Knabben · CC BY-SA · via GBIF

Alaska is not one climate

A single Alaska answer averages 28 counties whose growing seasons are 155 days apart — from 85 frost-free days in Southeast Fairbanks County to 240 in Sitka County. Which end of that your land sits nearer changes what mache can finish before the first hard freeze.

85 daysSoutheast Fairbanks County240 daysSitka County

The middle half of 28 counties runs 118196 days, with a median of 145 days — a 155-day span end to end.

Measured across 28 Alaska counties. NOAA Regional Climate Centers ACIS station record, 1991-2020, county 28°F killing freeze. 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.

Zone Comparison

Mache Needs

  • USDA Zones: Data pending
  • Frost-Free Days: 45+
  • Sun: Full Sun
  • Mature size: 6 in tall
  • Picking window: ~21 days of harvest
  • Drought tolerance: Low

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

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 6.07.5

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 Mache 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.

Frost hardiness

Mache takes cold down to about -5°F before a freeze kills it (FAO ECOCROP), so you can plant on the early side of Alaska'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

Mache is direct-sown where it grows rather than started under cover, so there is no seed-tray head start to bank — Alaska's dates above are the whole calendar for it. That makes the last-freeze date the binding constraint, and a warmer pocket of your own yard is worth more to this crop than it is to a transplanted one.

Days to maturity vs. the window

At 50 days to maturity (Growable Ground Plant Database), counting from the last hard freeze it ripens with 82 days to spare even in Alaska's tightest freeze scenario — room for a later start or a second sowing.

Timing tuned to sub-state frost dates — North Slope County, not the statewide average.

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

Frost-free days

Mache wants 45+ frost-free days; a typical Alaska site sees ~147 (NOAA Regional Climate Centers ACIS station record, 1991-2020). That leaves comfortable headroom for succession planting.

GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS station record, 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

Mache likes near-neutral soil (pH 6-7.5). That's the common-ground band across Alaska's permafrost and glacial silt — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 6.5 and 7 — 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, raised beds or amendment with compost solve it.

Your land, not the state average

Whether mache is safe to eat from Alaska soil is a block-by-block question, not a town-wide one — 15,895 documented contamination sites mean levels spike on some parcels and not the one next door. What mache takes up depends on the horizon its roots actually reach on your parcel, so only a test on your address settles it.

Check your parcel → Source: USDA NRCS SSURGO + EPA/state contamination databases.

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 mache 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 mache 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.

Federal record: High

We checked the federal record across Alaska15,895 documented sites across 7 of the 9 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 with clean imported soil grow well almost anywhere in the meantime.

Know before you grow — the guide

Sources Checked

across Alaska

Severity Distribution

across Alaska

High733Moderate11,479Low3,683

Highest-Severity Sites

Mining Sites · Past Producer
Mining Sites · Producer
Mining Sites · Past Producer
Mining Sites · Past Producer
Superfund · Superfund NPL

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, USGS1.8M documented sites tracked nationwide across 9 federal source types.

What Else to Consider for Mache 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

Growing mache here specifically

Because you eat the leaves of mache that sit in the soil, contamination matters more than for most crops — Alaska has 15,895 documented sites, and lead concentrates block by block, not town-wide.

Test your soil for lead first, and raise mache in clean imported soil if the reading is high. How to handle it →

What to actually do about these — and the constraints that apply to every Alaska grower, not just mache — is covered on the Alaska growing guide.

Timing shifts within Alaska

Alaska isn't one climate. In North Slope County, the last hard freeze (28°F) holds until about Jun 7 — roughly 33 days later than the recorded state median — so plant mache to your county's window, not the statewide date.

Mache needs about 45 days of frost-free season to complete its cycle. Even Southeast Fairbanks County — Alaska’s shortest season at 85 frost-free days — clears that by 40 days, so season length isn’t the constraint anywhere in Alaska. What varies is your own parcel.

Across Alaska’s 28 counties the frost-free season runs from 85 days in Southeast Fairbanks County to 240 days in Sitka County — a spread of 155 days, which is why a single statewide planting date misleads. The median Alaska county sees 147 frost-free days, leaving mache about 102 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"). Mache's 45-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

Mache draws honeybees (low value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, mache 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.

Alaska Cooperative Extension

For Alaska-specific cultivar recommendations, planting calendars, and pest pressure for mache, the canonical source is UAF Cooperative Extension Service. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Mache native to Alaska?

No — the USDA PLANTS Database lists Mache as introduced rather than native in the Lower 48, so it is not part of Alaska's native flora. It grows here as a garden plant; pairing it with a few Alaska natives keeps local pollinators fed too.

Looking for plants that belong here? The Alaska 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 Mache in Alaska

When can I plant Mache 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). Mache takes cold to about -5°F before a freeze kills it (FAO ECOCROP — the point where cold damages growing tissue, not a winter-survival floor), so plant on the early side of that window — even ahead of the final hard freeze.

Can Mache mature before first frost in Alaska?

Yes — Mache matures in 50 days (Growable Ground Plant Database), and Alaska's dependable hard-freeze-free window runs 132 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 82 days of margin. Plant once the last hard freeze has passed — two to three weeks later for anything tender — and it ripens ahead of the first fall freeze.

What hardiness zone is Mache grown in across Alaska?

Alaska spans USDA hardiness zones 1a-9a (USDA ARS PHZM 2023). Mache carries a range of zones Data pending, 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). Mache needs 45+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date. In cooler counties like North Slope, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Mache native to Alaska?

No — the USDA PLANTS Database lists Mache as introduced rather than native in the Lower 48, so it is not part of Alaska's native flora. It grows here as a garden plant; pairing it with a few Alaska natives keeps local pollinators fed too.

How should I amend the soil for Mache in Alaska?

Mache prefers pH 6-7.5 and well (dry spells) drainage (Growable Ground Plant Database). That sits in the common-ground band across Alaska soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.

Will Mache actually grow on my specific land in Alaska?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores mache against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.

Free Report

Check your specific parcel in Alaska

State-level data is a sketch. Your Growable Ground report scores mache against your parcel's exact soil, sun, drainage, and frost data — not zone averages.

Three things about your lot that Alaska mache averages can't show:

Your soil pHYour frost-free days — Alaska averages 147Your sun & shade

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 mache average

Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →

Cite this dataset

Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643

Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643

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