When to Plant Kale in Illinois
The toughest green in the garden. Kale laughs at frost and actually tastes sweeter after a cold snap.
The Short Answer
Illinois Frost Dates
Your planting dates depend on which part of Illinois you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Illinois (Chicago) | 5a, 5b | Apr 25 - May 10 | Oct 1 - Oct 15 |
| Central Illinois | 5b, 6a | Apr 15 - May 1 | Oct 5 - Oct 20 |
| Southern Illinois | 6b, 7a | Apr 1 - Apr 15 | Oct 15 - Nov 1 |
Kale Planting Schedule for Illinois
Northern Illinois (Chicago) (Zones 5a, 5b)
Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15
Central Illinois (Zones 5b, 6a)
Average last frost: Apr 15 - May 1 · Average first frost: Oct 5 - Oct 20
Southern Illinois (Zones 6b, 7a)
Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 15 - Nov 1
Growing Kale in Illinois
Kale in Illinois's Climate
Kale grows from early spring through late fall in your climate — frost-tolerant enough to be one of the first and last crops of the season. Fall-harvested kale sweetened by frost is the highlight. Summer kale production may pause during the hottest weeks (above 85°F) but typically resumes as temperatures moderate.
Soil Considerations for Illinois
Rich prairie soils — some of the most fertile in the country. Heavy clay in many areas. Well-suited for most vegetables.
Illinois Climate & Growing Season
Continental climate with four seasons. Hot, humid summers. Cold winters. Good growing season length in central and southern regions. Kale can handle frost well, which is an advantage in Illinois's climate. You can push planting dates earlier in spring and extend into fall.
Growing season length varies across Illinois: Northern Illinois (Chicago) (5a, 5b) has a last frost around Apr 25 - May 10, while Southern Illinois (6b, 7a) sees frost end around Apr 1 - Apr 15. This difference matters for kale — adjust your planting dates to match your specific region.
Growing Tips
Harvest outer leaves first, leaving the center to keep growing. Can survive temperatures down to 10°F with mulch protection.
Companion Planting
Plant kale alongside these companions for better growth:
Keep kale away from:
The Bottom Line
Last reviewed: March 29, 2026