fenugreek (Trigonella foenum-graecum), photographi

Can I Grow Fenugreek in Idaho?

USDA Zones 3b-8a · Plant zone range 6-11

Yes — Strong Match

fenugreek is grown as an annual, so season length decides it here, not a winter zone — and Idaho's typical season runs ~160 frost-free days against the ~90 fenugreek needs.

Fenugreek in Idaho — the short answer

Fenugreek in Idaho: grown in zones 6–11, full sun, against a state median of ~160 frost-free days.

Plant zones
Grown as an annual — see the growing season
Growing season, not a hardiness zone
Idaho zones
3b-8a
USDA PHZM 2023
Frost window
Apr 26 - May 17 – Oct 1 - Oct 17
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
94 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.

Score your parcel · free to start

Your yard isn't the whole zone.

Fenugreek is grown as an annual, so your winter zone isn't the deciding factor — your frost-free window is. A typical Idaho site runs ~160 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 fenugreek 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 parcel report in seconds — read in full free for your first 14 days

Idaho is not one climate

A single Idaho answer averages 44 counties whose growing seasons are 122 days apart — from 94 frost-free days in Valley County to 216 in Nez Perce County. Which end of that your land sits nearer changes what fenugreek can finish before the first hard freeze.

94 daysValley County216 daysNez Perce County

The middle half of 44 counties runs 133–174 days, with a median of 159 days — a 122-day span end to end.

Measured across 44 Idaho counties. NOAA Regional Climate Centers ACIS, 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.

Where in Idaho Fits Best

Even within Idaho's zones 3b-8a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for fenugreek (USDA PHZM 2023):

Zone Comparison

Fenugreek Needs

  • USDA Zones: 6-11
  • Frost-Free Days: 90+
  • Sun: Full Sun
  • Mature size: 2 ft tallWe haven't confirmed this against a published source yet.
  • Picking window: ~21 days of harvestWe haven't confirmed this against a published source yet.
  • Drought tolerance: MediumWe haven't confirmed this against a published source yet.

Idaho Has

  • USDA Zones: 3b-8a
  • Last Hard Freeze (28°F): Apr 26 - May 17
  • First Hard Freeze (28°F): Oct 1 - Oct 17
  • Annual Rainfall: 8-35 inches
  • Common Soils: Volcanic ash, Silt loam, Sandy loam

Plant Zone Range (zones 6-11)

6a
11b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 5.5 – 8.0

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 Fenugreek in Idaho

The frost window

Across Idaho, the last spring hard freeze (28°F) clears between Apr 26 and May 17, and the first fall hard freeze lands between Oct 1 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 137-day window you can count on — up to 174 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

Fenugreek takes cold down to about 28°F before a freeze kills it, so you can plant on the early side of Idaho'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. We haven't confirmed this against a published source yet.

When to start the seed

Fenugreek is direct-sown where it grows rather than started under cover, so there is no seed-tray head start to bank — Idaho'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 90 days to maturity (Growable Ground Plant Database), counting from the last hard freeze it ripens with 47 days to spare even in Idaho's tightest freeze scenario — room for a later start or a second sowing.

Timing tuned to sub-state frost dates — Valley 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

Fenugreek wants 90+ frost-free days; a typical Idaho site sees ~160 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

Growing degree days

Fenugreek needs ~1500 GDD (base 50°F) to ripen. We haven't confirmed this against a published source yet. The state median runs ~1187 GDD (from PRISM 1991-2020 climate normals), so Idaho's typical season runs short on heat — pick a south-facing site and consider season extension.

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

Fenugreek likes near-neutral soil (pH 5.5-8). That's the common-ground band across Idaho's volcanic ash and silt loam — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 6 and 7.5 — worth knowing before you decide whether a Idaho soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Idaho 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.

Your land, not the state average

Idaho's soils run mostly silt loam, but SSURGO maps the series, texture, and drainage under your exact parcel. What matters for fenugreek is the horizon its roots actually work, not the surface. That map unit, not the state average, decides how fenugreek performs.

Check your parcel → Source: USDA NRCS SSURGO.

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. Idaho soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant fenugreek 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 fenugreek goes in. What follows is Idaho’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 Idaho — and how to grow with it.

Federal record: High

We checked the federal record across Idaho — 10,406 documented sites across 7 of the 8 source types we track.

The most significant on record: 215 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Idaho 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.

Know before you grow — the guide

Sources Checked

across Idaho

Severity Distribution

across Idaho

High1,461Moderate4,227Low4,718

Highest-Severity Sites

Mining Sites · Past Producer
Mining Sites · Unknown
Mining Sites · Past Producer
Mining Sites · Past Producer
Mining Sites · Past Producer

A note from Gnorman

What an experienced grower watches for around here

In and around Idaho, two things run higher than the national average across Idaho — Mining (3,980 sites) and CAFO (218 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.

Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.

CAFO: CAFOs pose a different contamination profile than chemical sources.

Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.

Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.

Sources: EPA, USGS — 950K documented sites tracked nationwide across 8 federal source types.

What Else to Consider for Fenugreek in Idaho

The zone range tells you where fenugreek is grown — but Idaho growers also need to think about:

Short growing season at higher elevations

Arid conditions require irrigation in most of the state

Cold winter snaps can reach -30F in mountain valleys

Growing fenugreek here specifically

Idaho's soils run mostly silt loam (Mollisols), and whether that suits fenugreek's pH 5.5–8.0 preference comes down to your exact parcel, not the statewide picture.

Pull your parcel's SSURGO map unit, test pH, and amend toward fenugreek's 5.5–8.0 target before planting. How to handle it →

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

Timing shifts within Idaho

Idaho isn't one climate. In Valley County, the last hard freeze (28°F) holds until about Jun 14 — roughly 42 days later than the recorded state median — so plant fenugreek to your county's window, not the statewide date.

Fenugreek needs about 90 days of frost-free season to complete its cycle. Even Valley County — Idaho’s shortest season at 94 frost-free days — clears that by 4 days, so season length isn’t the constraint anywhere in Idaho. What varies is your own parcel.

Across Idaho’s 44 counties the frost-free season runs from 94 days in Valley County to 216 days in Nez Perce County — a spread of 122 days, which is why a single statewide planting date misleads. The median Idaho county sees 160 frost-free days, leaving fenugreek about 70 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"). Fenugreek's 90-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

Fenugreek draws honeybees and native bees (moderate value). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, fenugreek can only work that bloom inside Idaho's frost window — roughly 160 days, opening after the last 28°F freeze (Apr 26 - May 17) and closing at the first (Oct 1 - Oct 17), per NOAA Regional Climate Centers ACIS, 1991-2020. Pollinator value: We haven't confirmed this against a published source yet.

Recommended Fenugreek Varieties for Idaho

Idaho publishes no state variety trial for fenugreek, so we won't invent a "best for Idaho" list. Choose types rated to your USDA hardiness zone (3b-8a), and confirm winter survival and drainage against your own parcel.

Idaho Cooperative Extension

For Idaho-specific cultivar recommendations, planting calendars, and pest pressure for fenugreek, the canonical source is University of Idaho Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Fenugreek native to Idaho?

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

Looking for plants that belong here? The Idaho growing guide lists plants that USDA PLANTS records growing in Idaho and that Kew and NatureServe Explorer both list in its native range, leaving out any that NatureServe flags as exotic there or that our audit holds.

State records: USDA PLANTS Database state-distribution data (presence, not state-level nativity), accessed 2026-10-19.

Common Questions About Growing Fenugreek in Idaho

When can I plant Fenugreek in Idaho?

Idaho's last spring hard freeze (28°F) clears between Apr 26 and May 17, and the first fall hard freeze lands between Oct 1 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Time outdoor planting to after the last hard freeze for your specific site — a further two to three weeks for anything tender — and count back from those dates for transplant scheduling.

Can Fenugreek mature before first frost in Idaho?

Yes — Fenugreek matures in 90 days (Growable Ground Plant Database), and Idaho's dependable hard-freeze-free window runs 137 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 47 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 Fenugreek grown in across Idaho?

Idaho spans USDA hardiness zones 3b-8a (USDA ARS PHZM 2023). Fenugreek carries a range of zones 6-11, so the overlap zones are where outdoor growing is most reliable.

How many frost-free days does a typical Idaho site have?

A typical Idaho site sees ~160 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Fenugreek needs 90+ 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 Valley, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Fenugreek native to Idaho?

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

How should I amend the soil for Fenugreek in Idaho?

Fenugreek prefers pH 5.5-8 and well (dry spells) drainage. We haven't confirmed this against a published source yet. That sits in the common-ground band across Idaho soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.

Will Fenugreek actually grow on my specific land in Idaho?

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

Free to start

Check your specific parcel in Idaho

State-level data is a sketch. Your Growable Ground report scores fenugreek against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.

Three things about your lot that Idaho fenugreek averages can't show:

Your soil pHYour frost-free days — Idaho averages 160Your sun & shade

We read public map data around Idaho — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Idaho fenugreek 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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