When to plant kale in USDA Zone 5b

Plan your kale planting around local frost risk and soil temperature, then work backward from the harvest week your buyers need. The calendar below is a starting point, not a field-level weather forecast.

Chicago, Des Moines suburbs, central IL, upstate NY. Average last spring frost May 1, first fall frost October 6 — a 158-day frost-free season.

Zone fit: excellent
Kale is well suited to Zone 5b. Standard planting dates work with minor adjustments for microclimates.

Key dates

Start seeds indoors
March 20 – April 3
Direct-seed or transplant outdoors
March 27 – April 17
Expected first harvest
May 28 – June 25
Fall planting window
July 21 – August 11
Fall harvest window
September 21 – October 19

Windows are calculated from your zone's average frost dates. Adjust ±1 week for microclimates, elevation, and your own frost records.

Spacing and soil

Plant spacing
12″
Row spacing
24″
Seed depth
0.5″
Soil temperature
55–75°F
Frost tolerance
hardy
Days to harvest
55 days

Grower notes for Zone 5b

Harvest outer leaves and leave the growing tip — a single plant can produce for 3+ months.

Plant near: beets, onions, herbs

Keep away from: tomatoes

Other brassicas for Zone 5b

Same crop, other zones

Track your own plantings

BAU Farm Intelligence turns these windows into per-field tasks — indoor seed-start reminders, transplant dates, harvest projections — using your farm's actual frost history.