When to plant collards in USDA Zone 5a

Plan your collards 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.

Madison WI, Des Moines, southern MN, central MI. Average last spring frost May 8, first fall frost September 29 — a 144-day frost-free season.

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

Key dates

Start seeds indoors
March 27 – April 10
Direct-seed or transplant outdoors
April 3 – April 24
Expected first harvest
June 9 – July 7
Fall planting window
June 30 – July 21
Fall harvest window
September 5 – October 3

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
18″
Row spacing
24″
Seed depth
0.5″
Soil temperature
55–75°F
Frost tolerance
hardy
Days to harvest
60 days

Grower notes for Zone 5a

Southern staple. Flavor sweetens after two hard frosts — fall crop always beats spring for quality.

Plant near: onions, beets, carrots

Keep away from: tomatoes

Other brassicas for Zone 5a

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.