Frost dates · USDA zone 6a

Frost dates for Champaign, IL

Champaign, IL sees its last 32 °F night of spring around April 15 and its first of fall around October 24 — a 190-day freeze-free season in a typical year.

Apr 15Last spring frostmedian · 1 in 10 years after Apr 29
Oct 24First fall frostmedian · 1 in 10 years before Oct 11
190Freeze-free daysmedian year · ≥171 in 9 of 10
6aUSDA zone2023 map · ZIP 61821
Build a Champaign sauce plan →

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

OddsLast spring freeze afterFirst fall freeze before
9 years in 10Apr 1Nov 5
Median — 1 year in 2Apr 15Oct 24
1 year in 10Apr 29Oct 11

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: 190 days median, at least 171 in 9 years of 10, at least 209 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 4 and first of Nov 2.

Champaign planting calendar, 2027

Every row runs from the median last frost (Apr 15) and median first frost (Oct 24) above, using each cultivar's days to maturity. Same engine as the Plan Builder.

CropStart indoorsTransplant / plantFirst harvestDays
Hardneck GarlicSiberian (porcelain hardneck)—Oct 15prior fallJun 12240 from sow
Spanish OnionYellow Sweet Spanish (long-day)Jan 21Mar 18Jul 6110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowApr 15May 1530 from sow
CilantroSlow Bolt (Coriandrum sativum)Apr 1Apr 1May 1645 from sow
Genovese BasilGenoveseMar 18Apr 29Jun 2860 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Feb 18Apr 22Jul 675 from transplant
HabaneroOrange Habanero (Capsicum chinense)Feb 4Apr 29Aug 295 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Feb 18Apr 22Jul 675 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Feb 18Apr 22Jul 1180 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Feb 18Apr 22Jul 1180 from transplant
Nantes CarrotScarlet NantesApr 1Apr 1Jun 1070 from sow
TomatilloToma VerdeMar 4Apr 22Jul 170 from transplant
Roma TomatoRoma VF (determinate paste)Mar 4Apr 22Jul 675 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Mar 4Apr 22Jul 1180 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.

Champaign frost questions

When is the last frost in Champaign, IL?

The median last 32 °F freeze at CHAMPAIGN 3S, IL is April 15: half of years see a later one. One year in ten, a freeze still comes after April 29; nine years in ten, it comes after April 1. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in Champaign, IL?

The median first 32 °F freeze of fall is October 24. One year in ten it arrives before October 11; nine years in ten, before November 5.

How long is the growing season in Champaign, IL?

190 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 171 days; one year in ten, at least 209 days.

What growing zone is Champaign, IL?

USDA hardiness zone 6a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 61821. 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 Champaign, IL?

Start Roma VF (determinate paste) seeds indoors around Mar 4 and transplant around Apr 22, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Apr 29. First ripe fruit lands around Jul 6.

When should I plant peppers in Champaign, IL?

Sow jalapeño indoors on a heat mat around Feb 18; transplant no earlier than Apr 22, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 6.

Nearby in Illinois

All Illinois frost dates → · How frost-date math drives a sowing calendar →