USDA zone 6a in Nebraska
USDA plant hardiness zone 6a covers 41 locations across Nebraska (average annual extreme minimum −10 to −5 °F): Adams, NE, Alma, NE, Alvo, NE, Beatrice, NE, Crab Orchard, NE, Crete, NE, and 35 more. Average last spring frost across this group ranges April 15 (Omaha) to May 4 (Stamford), and growing seasons run 150–187 days (Stamford to Omaha) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Nebraska location's own frost dates; the printable planting calendar uses Republican, this group's median-season location.
- USDA zone
- 6a−10 to −5 °F
- Last frost range
- Apr 15–May 4avg, 32°F
- First frost range
- Oct 4–Oct 21avg, 32°F
- Growing season range
- 150–187days
Locations in this group
Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.
| Location | Also covers | Nearest station | Last frost | First frost | Season (days) |
|---|---|---|---|---|---|
| Adams | Liberty, Lewiston, Filley, Virginia | Virginia | Apr 22 | Oct 20 | 179 |
| Alma | Orleans, Wilcox | Ragan | Apr 24 | Oct 18 | 174 |
| Alvo | Murdock | Ashland #2 | Apr 23 | Oct 16 | 175 |
| Beatrice | Blue Springs, De Witt, Plymouth, Odell, Cortland, Pickrell | Beatrice 1n | Apr 24 | Oct 15 | 172 |
| Crab Orchard | — | Tecumseh 1s | Apr 26 | Oct 10 | 164 |
| Crete | Hickman, Wilber, Dorchester, Firth, Clatonia, Hallam, +2 more | Crete 4ese | Apr 23 | Oct 12 | 170 |
| Danbury | — | Mccook Muni Ap | May 1 | Oct 9 | 160 |
| Elmwood | Palmyra, Unadilla, Dunbar, Douglas, Otoe, Avoca | Syracuse | Apr 25 | Oct 11 | 168 |
| Exeter | Grafton, Cordova | Fairmont | Apr 25 | Oct 14 | 170 |
| Fairbury | Endicott, Diller, Reynolds, Steele, Mahaska, Daykin, +1 more | Fairbury 5s | Apr 25 | Oct 15 | 169 |
| Falls | Sabetha, Rulo, Salem, Craig, Verdon, Dawson, +1 more | Falls City Brenner Fld | Apr 18 | Oct 17 | 180 |
| Franklin | Bloomington, Hildreth, Upland, Campbell, Riverton, Naponee | Franklin #2 | Apr 30 | Oct 8 | 161 |
| Friend | Western | Friend 3e | Apr 26 | Oct 13 | 169 |
| Geneva | Shickley, Tobias, Milligan, Ohiowa, Strang | Geneva | Apr 20 | Oct 18 | 178 |
| Guide Rock | — | Red Cloud | May 1 | Oct 5 | 157 |
| Hastings | — | Hastings Muni Ap | Apr 22 | Oct 16 | 176 |
| Hebron | Carleton, Davenport, Chester, Deshler, Belvidere, Alexandria, +4 more | Hebron | Apr 24 | Oct 15 | 172 |
| Holdrege | Bertrand, Funk, Atlanta | Holdrege | May 2 | Oct 11 | 162 |
| Humboldt | Pawnee, Table Rock, Axtell, Du Bois, Summerfield, Bern, +2 more | Pawnee City | Apr 22 | Oct 15 | 173 |
| Lincoln | Walton, Bennet, Eagle, Panama, Cheney | Lincoln 8 Ene | Apr 27 | Oct 10 | 164 |
| Lincoln | Yankee Hill, Waverly, Emerald, Raymond | Lincoln Muni Ap | Apr 24 | Oct 13 | 171 |
| McCook | — | Mc Cook | May 2 | Oct 9 | 159 |
| Nebraska | Murray | Nebraska City 2nw | Apr 18 | Oct 19 | 182 |
| Omaha | Bennington, Waterloo, Kennard, Washington | Valley Nws | Apr 15 | Oct 21 | 187 |
| Omaha | Council Bluffs, Carter Lake, Bennington | Omaha Eppley Airfield | Apr 18 | Oct 21 | 185 |
| Omaha | Bellevue, Offutt AFB | Springfield 7e | Apr 17 | Oct 19 | 183 |
| Omaha | Chalco, Richfield, Boys | Gretna 4ne | Apr 21 | Oct 18 | 179 |
| Omaha | — | Omaha #1 | Apr 16 | Oct 18 | 183 |
| Oxford | Edison | Oxford 6nnw | May 1 | Oct 8 | 161 |
| Plattsmouth | Glenwood | Glenwood 3sw | Apr 23 | Oct 11 | 170 |
| Pleasant Dale | — | Seward | Apr 26 | Oct 12 | 169 |
| Republican * | — | Harlan Co Lake | Apr 25 | Oct 14 | 170 |
| Roca | Denton | Lincoln 11 Sw | Apr 22 | Oct 14 | 174 |
| Shubert | Stella | Auburn 5 Ese | Apr 24 | Oct 10 | 167 |
| Stamford | — | Beaver City | May 4 | Oct 4 | 150 |
| Superior | Nelson, Hardy, Ruskin, Oak | Superior | Apr 29 | Oct 10 | 162 |
| Sutton | Edgar, Clay Center, Fairfield, Harvard, Ong, Glenvil, +2 more | Clay Ctr | Apr 19 | Oct 20 | 181 |
| Trenton | — | Trenton Dam 1n | Apr 29 | Oct 13 | 166 |
| Trumbull | Inland | Hastings 4n | Apr 25 | Oct 14 | 171 |
| Weeping Water | Manley | Weeping Water | Apr 23 | Oct 16 | 175 |
| Wilsonville | Lebanon | Cambridge | May 3 | Oct 5 | 156 |
* Republican is this group's median-season location — the calendar below is computed from its data.
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Planting calendar (Republican, representative)
Computed from Republican's average frost dates — the median-season location in this Nebraskazone 6a group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting | Season fit |
|---|---|---|---|---|---|---|
| Tomato | Tender | Feb 28 – Mar 14 | May 2 – May 9 | Jul 1 – Jul 21 | — | matures comfortably |
| Pepper | Very tender | Feb 14 – Feb 28 | May 9 – May 16 | Jul 8 – Aug 7 | — | matures comfortably |
| Cucumber | Tender | Mar 28 – Apr 4 | May 2 – May 9 | Jun 21 – Jul 11 | — | matures comfortably |
| Summer squash / zucchini | Tender | — | May 2 – May 9 | Jun 16 – Jul 1 | — | matures comfortably |
| Bush bean | Tender | — | May 2 – May 9 | Jun 21 – Jul 1 | Aug 15 – Aug 25 | matures comfortably |
| Sweet corn | Tender | — | Apr 25 – May 9 | Jun 24 – Jul 24 | — | matures comfortably |
| Basil | Very tender | Mar 14 – Mar 28 | May 2 – May 9 | Jun 1 – Jun 16 | — | matures comfortably |
| Lettuce | Half-hardy | Mar 14 – Mar 28 | Mar 28 – Apr 11 | May 12 – May 27 | Aug 1 – Aug 16 | matures comfortably |
| Pea | Hardy | — | Mar 14 – Mar 28 | May 8 – May 23 | Jul 22 – Aug 6 | matures comfortably |
| Spinach | Hardy | — | Mar 14 – Mar 28 | Apr 23 – May 3 | Aug 11 – Aug 21 | matures comfortably |
| Carrot | Half-hardy | — | Apr 4 – Apr 11 | Jun 3 – Jun 23 | Jul 12 – Aug 1 | matures comfortably |
| Broccoli | Half-hardy | Feb 28 – Mar 14 | Mar 28 – Apr 11 | May 22 – Jun 11 | Jul 17 – Aug 6 | matures comfortably |
Which crops fit this growing season
Using Republican's own 170-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.
Frost & freeze dates (Republican)
From NOAA's 1991–2020 Climate Normals at station USC00253595. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | May 3 | May 15 | Oct 5 | Oct 17 | 153 |
| 32°F (freeze) | Apr 25 | May 7 | Oct 14 | Oct 25 | 170 |
| 28°F | Apr 14 | Apr 29 | Oct 23 | Nov 4 | 190 |
| 24°F | Apr 4 | Apr 20 | Oct 31 | Nov 14 | 208 |
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 41 locations is 3,470; Republican's own reading is shown below.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 3,579 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 5,843 | cool-season crops (brassicas, greens) |
Hardiness zone 6a in Nebraska
Zone 6a means an average annual extreme minimum winter temperature of about −10 to −5 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Nebraska spans 3 hardiness zones in this dataset — see all Nebraska locations for the full range, including zones5a, 5b.
Explore zone 6a in other states at zone 6a, or see all USDA hardiness zones.
Frequently asked questions
- What does USDA hardiness zone 6a mean in Nebraska?
- Zone 6a means an average annual extreme minimum winter temperature of −10 to −5 °F — the standard USDA measure of which perennials survive winter. 41 locations in Nebraska fall in this zone. It does not set planting dates; see the frost calendar below for that.
- Where in Nebraska's zone 6a is the growing season longest?
- Omaha runs the longest season on this page at about 187 days; Stamford is shortest at about 150 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
- When should I plant tomatoes in Nebraska's zone 6a?
- Using Republican's frost dates (this page's median-season location): start seeds indoors about Feb 28 – Mar 14, then transplant outside about May 2 – May 9. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
- Does every location in Nebraska's zone 6a have the same frost dates?
- No — they do not all share a weather station, so frost dates vary by a week or more across the 41 locations listed (see the table above for each location's own dates).
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.