Can I Grow Collard Greens in Nebraska?

Collard Greens in Nebraska — the short answer

Nebraska is not one climate

Where in Nebraska Fits Best

Even within Nebraska's zones 4b-6a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for collard greens (USDA PHZM 2023):

Zone Comparison

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 Collard Greens in Nebraska

Timing tuned to sub-state frost dates — Sioux 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 collard greens survives winter here. Whether the season is long enough — and warm enough — is a different question.

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

Collard Greens tolerates a wide pH range (pH 5.5-8.5) — 3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Nebraska. 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 7 — worth knowing before you decide whether a Nebraska soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Nebraska 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. Nebraska soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant collard greens 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 collard greens goes in. What follows is Nebraska’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 Nebraska — and how to grow with it.

Federal record: High

We checked the federal record across Nebraska — 10,663 documented sites across 8 of the 9 source types we track.

The most significant on record: 162 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Nebraska 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.

See every recorded site across Nebraska on the mapKnow before you grow — the guide

Explore the live map

Nitrate4,328Brownfields2,675Underground Storage Tanks2,179CAFO700Toxics Release Inventory569

Sources Checked

across Nebraska

Nitrate Monitoring

4,328

Brownfields

2,675

Underground Storage Tanks

2,179

Concentrated Animal Feeding

700

Toxics Release Inventory

569

Superfund

162

PFAS Sampling

49

Mining Sites

1

Severity Distribution

across Nebraska

High67Moderate6,955Low3,641

Highest-Severity Sites

10TH Street Site

Superfund · Superfund NPL

Alliance, City of

PFAS Sampling · PFAS Detected

Alma Ne, City of

PFAS Sampling · PFAS Detected

Arlington, Village of

PFAS Sampling · PFAS Detected

Auburn, City of

PFAS Sampling · PFAS Detected

A note from Gnorman

What an experienced grower watches for around here

In and around Nebraska, two things run higher than the national average across Nebraska — CAFO (700 sites) and Nitrate (4,328 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.

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

Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.

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

Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).

grow under coverwork your in-ground beds wiselyread your soil before you plantbuild soil that holds onto nitrogenSee what's flagged near Nebraska

Explore the contamination map around Nebraska

Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.

What Else to Consider for Collard Greens in Nebraska

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

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

Timing shifts within Nebraska

Nebraska isn't one climate. In Sioux County, the last hard freeze (28°F) holds until about May 14 — roughly 25 days later than the recorded state median — so plant collard greens to your county's window, not the statewide date.

Collard Greens needs about 60 days of frost-free season to complete its cycle. Even Sioux County — Nebraska’s shortest season at 134 frost-free days — clears that by 74 days, so season length isn’t the constraint anywhere in Nebraska. What varies is your own parcel.

Across Nebraska’s 93 counties the frost-free season runs from 134 days in Sioux County to 207 days in Sarpy County — a spread of 73 days, which is why a single statewide planting date misleads. The median Nebraska county sees 181 frost-free days, leaving collard greens about 121 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"). Collard Greens's 60-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

Collard Greens draws honeybees and native bees (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, collard greens can only work that bloom inside Nebraska's frost window — roughly 181 days, opening after the last 28°F freeze (Apr 12 - Apr 26) and closing at the first (Oct 15 - Oct 21), per NOAA Regional Climate Centers ACIS, 1991-2020.

Nebraska Cooperative Extension

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

Is Collard Greens native to Nebraska?

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

Looking for plants that belong here? The Nebraska 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 Collard Greens in Nebraska