Kewanee, IL planting zone & frost dates

Kewanee is in USDA hardiness zone 5b. The last spring frost usually comes around April 24 and the first fall frost around October 17, for a growing season of about 175 days.

USDA hardiness zone5bavg. extreme winter low -15°F to -10°F
Average last spring frostApril 2490% chance of no frost after May 8
Average first fall frostOctober 1710% chance of frost by October 3
Growing season175 daysfrost-free days in an average year

Planting calendar for Kewanee

Dates are counted from the average last spring frost (April 24) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.

CropWhen
TomatoesStart seeds indoors: Feb 27 – Mar 13
Transplant outdoors: May 1 – May 8
PeppersStart seeds indoors: Feb 13 – Feb 27
Transplant outdoors: May 8 – May 15
EggplantStart seeds indoors: Feb 13 – Feb 27
Transplant outdoors: May 8 – May 15
BroccoliStart seeds indoors: Feb 13 – Feb 27
Transplant outdoors: Mar 27 – Apr 10
CabbageStart seeds indoors: Feb 13 – Feb 27
Transplant outdoors: Mar 27 – Apr 10
Onions (sets)Plant outdoors: Mar 27 – Apr 10
PeasSow outdoors: Mar 13 – Mar 27
SpinachSow outdoors: Mar 13 – Mar 27
LettuceSow outdoors: Mar 27 – Apr 10
CarrotsSow outdoors: Mar 27 – Apr 10
PotatoesPlant outdoors: Mar 27 – Apr 10
BeansSow outdoors: May 1 – May 8
Sweet cornSow outdoors: May 1 – May 8
CucumbersSow outdoors: May 1 – May 8
Squash & zucchiniSow outdoors: May 1 – May 8
BasilStart seeds indoors: Mar 13 – Mar 27
Transplant outdoors: May 1 – May 8

Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Aug 22 (8 weeks before the average first fall frost on Oct 17).

Useful for zone 5b gardens

As an Amazon Associate, FrostZoneMap earns from qualifying purchases, at no extra cost to you.

Frost risk in detail

90% chance50% chance10% chance
Last 32°F frost in spring is afterApr 10Apr 24May 8
First 32°F frost in fall is beforeOct 29Oct 17Oct 3

How to read it: in spring there is a 10% chance of a frost after May 8, so that is a safe date for tender plants. In fall there is a 10% chance of frost before October 3. A hard freeze (28°F) usually ends around April 13.

Hardiness zone by ZIP code in Kewanee

Nearby cities

All cities in Illinois → · Other zone 5b cities →

Questions

What growing zone is Kewanee, IL?

Kewanee is in USDA Plant Hardiness Zone 5b (average extreme winter low -15°F to -10°F), according to the USDA 2023 map.

When is the last frost in Kewanee?

The average last spring frost (32°F) in Kewanee is April 24. There is still a 10% chance of frost until May 8.

When can I plant tomatoes in Kewanee?

Transplant tomatoes outdoors 1–2 weeks after the average last frost: around May 1 – May 8. Start seeds indoors 6–8 weeks before the last frost.

Frost dates: NOAA U.S. Climate Normals 1991–2020, station Kewanee 1 E, IL (USC00114710), 2.1 km (1.3 mi) from the city center, elevation 238 m, based on 28 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.