USDA hardiness zone
Zone 5b
Rolled up from the 2,952 ZIP codes in our data that are classified zone 5b, covering 2,474 nurseries and garden centers across 615 cities we track in this zone.
Average minimum winter temperature
-15°F
Last spring frost range
Apr 8–Jun 21
First fall frost range
Aug 31–Nov 4
Average frost-free growing season
159 days
Average monthly temperature
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 22.2° | 25.2° | 35.1° | 46.3° | 57.4° | 66.9° | 71.4° | 69.6° | 62.1° | 49.9° | 37.6° | 27.2° |
NOAA 1991–2020 Climate Normals, averaged across this zone's member ZIPs.
Crops by frost hardiness
What grows here, and when
This zone's own last-frost dates range across Apr 8–Jun 21. Hardy and semi-hardy crops can go in before that date; tender and very-tender crops need to wait until after it. See each crop's own guide for exact windows at a specific location in this zone.
Planting windows and crop timing here are computed from USDA/NOAA climate data and the university extension sources cited below, not a site visit or soil test. Treat this as a starting point: local conditions vary, and a local nursery or extension office can advise on your exact site. See our full Disclaimer.
Hardy (49)
- Apple (bare-root fruit tree)
- Apricot (bare-root fruit tree)
- Asparagus
- Bachelor's Button (Cornflower)
- Bare-root rose
- Blackberry
- Blueberry
- Broccoli
- Brussels Sprouts
- Cabbage
- Calendula
- Catnip/Catmint
- Cherry (sweet/tart, bare-root fruit tree)
- Chives
- Collards
- Currant
- Deciduous shade tree (generic, e.g. maple/oak, bare-root or B&B)
- Elderberry
- Evergreen shrub (B&B/potted, e.g. arborvitae, boxwood)
- Flowering deciduous shrub (generic, e.g. lilac/forsythia)
- Garden Peas
- Garlic
- Gooseberry
- Kale
- Kohlrabi
- Larkspur
- Lavender
- Lettuce
- Mint
- Onion (bulb)
- Oregano
- Peach (bare-root fruit tree)
- Pear (bare-root fruit tree)
- Plum (bare-root fruit tree)
- Radish
- Raspberry
- Rhubarb
- Rutabaga
- Sage
- Snapdragon
- Snow Peas
- Spinach
- Strawberry
- Sweet Alyssum
- Sweet Pea
- Table/Bunch Grape
- Tarragon
- Thyme
- Turnip
Semi-hardy (16)
Tender (20)
Zone 5b means an average annual extreme minimum winter temperature of -15°F to -10°F on the 2023 USDA Plant Hardiness Zone Map (USDA/ARS with the PRISM Climate Group at Oregon State University, 1991-2020 records). Every ZIP in this rollup carries its zone matched by centroid against the map, not by its polygon boundary, via phzmapi.org's ZIP-level derivation.
The first-frost range above spans about nine weeks across this zone's own ZIPs, wide enough that a fall crop planted on this page's own median date could be two months early or right on time depending which of this zone's ZIPs you actually garden in.
We track nurseries across 16 states in zone 5b, from Alaska and Idaho to Maine, with Madison, WI carrying the most, followed by Appleton and Green Bay, WI. This zone is also this directory's own representative ZIP for the cold band on the monthly planting guides.
Cities we track in zone 5b
- Madison, WI (51)
- Appleton, WI (40)
- Green Bay, WI (37)
- Fort Collins, CO (32)
- Waukesha, WI (30)
- Fort Plain, NY (28)
- Des Moines, IA (26)
- Rockford, IL (23)
- Longmont, CO (23)
- Missoula, MT (23)
- Idaho Falls, ID (23)
- Springville, NY (22)
Nearby zones
All zones
USDA 2023 Plant Hardiness Zone Map (zone boundaries, via the phzmapi.org ZIP-level derivation) and NOAA 1991–2020 Climate Normals (frost dates, growing season, monthly temperatures).