Frost dates · USDA zone 5a
Frost dates for Madison, WI
Madison, WI sees its last 32 °F night of spring around May 1 and its first of fall around October 9 — a 161-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Apr 18 | Oct 24 |
| Median — 1 year in 2 | May 1 | Oct 9 |
| 1 year in 10 | May 17 | Sep 26 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 161 days median, at least 140 in 9 years of 10, at least 179 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Apr 20 and first of Oct 20.
Madison planting calendar, 2027
Every row runs from the median last frost (May 1) and median first frost (Oct 9) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Feb 6 | Apr 3 | Jul 22 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | May 1 | May 31 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Apr 17 | Apr 17 | Jun 1 | 45 from sow |
| Genovese BasilGenovese | Apr 3 | May 15 | Jul 14 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Mar 6 | May 8 | Jul 22 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Feb 20 | May 15 | Aug 18 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Mar 6 | May 8 | Jul 22 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Mar 6 | May 8 | Jul 27 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Mar 6 | May 8 | Jul 27 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Apr 17 | Apr 17 | Jun 26 | 70 from sow |
| TomatilloToma Verde | Mar 20 | May 8 | Jul 17 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Mar 20 | May 8 | Jul 22 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Mar 20 | May 8 | Jul 27 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Madison grow?
Each sauce, scheduled for a Madison container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Madison frost questions
When is the last frost in Madison, WI?
The median last 32 °F freeze at UW ARBORETUM - MADISON, WI is May 1: half of years see a later one. One year in ten, a freeze still comes after May 17; nine years in ten, it comes after April 18. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Madison, WI?
The median first 32 °F freeze of fall is October 9. One year in ten it arrives before September 26; nine years in ten, before October 24.
How long is the growing season in Madison, WI?
161 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 140 days; one year in ten, at least 179 days.
What growing zone is Madison, WI?
USDA hardiness zone 5a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 53792. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Madison, WI?
Start Roma VF (determinate paste) seeds indoors around Mar 20 and transplant around May 8, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for May 17. First ripe fruit lands around Jul 22.
When should I plant peppers in Madison, WI?
Sow jalapeño indoors on a heat mat around Mar 6; transplant no earlier than May 8, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 22.
Nearby in Wisconsin
- Janesvillelast frost Apr 26
- Waukeshalast frost Apr 30
- Brookfieldlast frost Apr 26
- Fond du Laclast frost May 1
- Wauwatosalast frost Apr 26
- West Allislast frost Apr 26
All Wisconsin frost dates → · How frost-date math drives a sowing calendar →