Egyptian walking onion (Allium proliferum), photographi

Can I Grow Egyptian Walking Onion in New Hampshire?

USDA Zones 3b-6b · Plant zone range 3-9

Yes — Strong Match

Egyptian walking onion (zones 3-9) covers every zone New Hampshire contains (3b-6b), so hardiness is not what limits it anywhere in the state.

Egyptian Walking Onion in New Hampshire — the short answer

Egyptian Walking Onion in New Hampshire: hardy in zones 3–9, full sun, against a state median of ~171 frost-free days.

Plant zones
3-9
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
New Hampshire zones
3b-6b
USDA PHZM 2023
Frost window
Apr 22 - May 4 – Oct 10 - Oct 21
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
145 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Days to maturity
240 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.

New Hampshire spans zones 3b-6b, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score egyptian walking onion against your land's actual soil, sun, and frost.

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

New Hampshire is not one climate

A single New Hampshire answer averages 10 counties whose growing seasons are 43 days apart — from 145 frost-free days in Coos County to 188 in Rockingham County. Which end of that your land sits nearer changes what egyptian walking onion can finish before the first hard freeze.

145 daysCoos County188 daysRockingham County

The middle half of 10 counties runs 159183 days, with a median of 169 days — a 43-day span end to end.

Measured across 10 New Hampshire 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 New Hampshire Fits Best

Even within New Hampshire's zones 3b-6b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for egyptian walking onion (USDA PHZM 2023):

Zone Comparison

Egyptian Walking Onion Needs

  • USDA Zones: 3-9
  • Frost-Free Days: 120+
  • Sun: Full Sun
  • Mature size: 2.5 ft tall
  • Picking window: ~60 days of harvest
  • Drought tolerance: Medium

New Hampshire Has

  • USDA Zones: 3b-6b
  • Last Hard Freeze (28°F): Apr 22 - May 4
  • First Hard Freeze (28°F): Oct 10 - Oct 21
  • Annual Rainfall: 36-50 inches
  • Common Soils: Glacial till, Sandy loam, Rocky loam

Plant Zone Range (zones 3-9)

3a
9b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.57.5

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 Egyptian Walking Onion in New Hampshire

The frost window

Across New Hampshire, the last spring hard freeze (28°F) clears between Apr 22 and May 4, and the first fall hard freeze lands between Oct 10 and Oct 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 159-day window you can count on — up to 182 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

Egyptian Walking Onion takes cold down to about 23°F before a freeze kills it (FAO ECOCROP), so you can plant on the early side of New Hampshire'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.

Days to maturity vs. the window

At 240 days to maturity (Growable Ground Plant Database), even New Hampshire's kindest 182-day season runs short — challenging without season extension. An indoor start plus row cover on both shoulders of the season closes the gap.

Timing tuned to sub-state frost dates — Coos 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

The zone check says egyptian walking onion survives winter here. Whether the season is long enough — and warm enough — is a different question.

Frost-free days

Egyptian Walking Onion wants 120+ frost-free days; a typical New Hampshire site sees ~171 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves a workable window — start indoors to bank time.

Growing degree days

Egyptian Walking Onion needs ~1200 GDD (base 50°F) to ripen. The state median runs ~1870 GDD (from PRISM 1991-2020 climate normals), so New Hampshire'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

Egyptian Walking Onion 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 New Hampshire. 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 New Hampshire soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your New Hampshire 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 egyptian walking onion is safe to eat from New Hampshire soil is a block-by-block question, not a town-wide one — 10,091 documented contamination sites mean levels spike on some parcels and not the one next door. Egyptian Walking Onion roots to about 19 inches, so it is the top 19 inches under your address that decide what it takes up, 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. New Hampshire soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant egyptian walking onion 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 egyptian walking onion goes in. What follows is New Hampshire’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 New Hampshire — and how to grow with it.

Federal record: High

We checked the federal record across New Hampshire10,091 documented sites across 8 of the 9 source types we track.

The most significant on record: 82 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

New Hampshire 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 New Hampshire

Severity Distribution

across New Hampshire

High85Moderate3,894Low6,112

Highest-Severity Sites

PFAS Sampling · PFAS Detected
Superfund · Superfund NPL
Superfund · Superfund NPL
PFAS Sampling · PFAS Detected
Mining Sites · Past Producer

Know Before You Grow

  • Underground tanks leak petroleum as they age — near a former filling station, test the soil.
  • Near a brownfield, raised beds of imported soil give your food clean ground.
  • On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.

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

What Else to Consider for Egyptian Walking Onion in New Hampshire

Zone compatibility tells you about winter cold survival — but New Hampshire growers also need to think about:

Very short season in the White Mountains (80-100 frost-free days)

Rocky glacial soils throughout the state

Harsh winters with deep snow cover

Growing egyptian walking onion here specifically

Egyptian Walking Onion grows its edible bulb in the soil itself, so on any of New Hampshire's 10,091 documented contamination sites it can carry up lead you'd then eat.

Keep egyptian walking onion in raised beds of screened clean soil and confirm your parcel's lead level before the first crop. How to handle it →

What to actually do about these — and the constraints that apply to every New Hampshire grower, not just egyptian walking onion — is covered on the New Hampshire growing guide.

Timing shifts within New Hampshire

New Hampshire isn't one climate. In Coos County, the last hard freeze (28°F) holds until about May 13 — roughly 16 days later than the recorded state median — so plant egyptian walking onion to your county's window, not the statewide date.

Egyptian Walking Onion needs about 120 days of frost-free season to complete its cycle. Even Coos County — New Hampshire’s shortest season at 145 frost-free days — clears that by 25 days, so season length isn’t the constraint anywhere in New Hampshire. What varies is your own parcel.

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"). Egyptian Walking Onion'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

Egyptian Walking Onion 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, egyptian walking onion can only work that bloom inside New Hampshire's frost window — roughly 171 days, opening after the last 28°F freeze (Apr 22 - May 4) and closing at the first (Oct 10 - Oct 21), per NOAA Regional Climate Centers ACIS, 1991-2020.

Good to Know Before You Plant Egyptian Walking Onion

Egyptian Walking Onion is listed as toxic to dogs, cats (all) at a moderate level (ASPCA). Most listed plants only cause brief upset — a raised bed or a fenced corner usually keeps curious pets clear. Worth knowing for placement: in New Hampshire this is a one-season plant and the first hard freeze (Oct 10 - Oct 21) takes it down, so the exposure above is a summer-long one rather than something standing in the bed all year.

New Hampshire Cooperative Extension

For New Hampshire-specific cultivar recommendations, planting calendars, and pest pressure for egyptian walking onion, the canonical source is UNH Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Common Questions About Growing Egyptian Walking Onion in New Hampshire

When can I plant Egyptian Walking Onion in New Hampshire?

New Hampshire's last spring hard freeze (28°F) clears between Apr 22 and May 4, and the first fall hard freeze lands between Oct 10 and Oct 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Egyptian Walking Onion takes cold to about 23°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 Egyptian Walking Onion mature before first frost in New Hampshire?

Egyptian Walking Onion needs 240 days to mature (Growable Ground Plant Database), and even New Hampshire's longest typical season runs 182 days (NOAA Regional Climate Centers ACIS, 1991-2020) — challenging without season extension. An indoor start plus row cover on both season shoulders closes the gap.

What hardiness zone is Egyptian Walking Onion grown in across New Hampshire?

New Hampshire spans USDA hardiness zones 3b-6b (USDA ARS PHZM 2023). Egyptian Walking Onion carries a range of zones 3-9, so the overlap zones are where outdoor growing is most reliable.

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

A typical New Hampshire site sees ~171 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Egyptian Walking Onion needs 120+ 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 Coos, the freeze-free season runs shorter than the state average, so verify your own county's window.

How should I amend the soil for Egyptian Walking Onion in New Hampshire?

Egyptian Walking Onion 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 New Hampshire site — amend for drainage and organic matter first.

Will Egyptian Walking Onion actually grow on my specific land in New Hampshire?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores egyptian walking onion 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 New Hampshire

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

Three things about your lot that New Hampshire egyptian walking onion averages can't show:

Your soil pHYour frost-free days — New Hampshire averages 171Your sun & shade

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

25+ data sources read at your address, not the New Hampshire egyptian walking onion average

Explore More

Explore New Hampshire county by county

New Hampshire carries 10 counties with their own USDA zone — a sample of the growing pages for egyptian walking onion there:

Where else egyptian walking onion grows

Egyptian Walking Onion's zone band crosses state lines — these are the states closest to New Hampshire 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 New Hampshire

New Hampshire has a growing page for 806 plants — a rotating sample of the rest of the shelf.

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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