When to plant sweet corn in zone 6a
In zone 6a, where the last spring frost typically comes around April 29, sow outdoors April 29 to May 13.
The zone 6a schedule for sweet corn
- Sow outdoors
- April 29 to May 13
- Safest planting date (10% frost risk)
- May 14
- First harvest, roughly
- June 28 to August 21
From the median frost dates of the NOAA stations assigned to the 4,514 ZIP codes in zone 6a, and the timing recommended by Cooperative Extension guides for sweet corn.
Frost risk in zone 6a
Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 6a, the typical last frost ranges from about April 16 in the earliest tenth of ZIP codes to May 11 in the latest tenth, and the first fall frost from October 4 to October 24. For a typical place in the zone:
- April 16Risky: a later frost happens in 9 years out of 10
- April 29Typical: frost after this date in half of years
- May 14Safe: a later frost only 1 year in 10
Sweet Corn are killed by frost, so if you want to be safe, plant out after the safe date rather than the typical one, or be ready to cover plants on a cold night.
Your dates for sweet corn
Set your ZIP code at the top of the page and we will work out when to plant sweet corn where you live, from the frost records of the nearest NOAA weather station. Your ZIP code is remembered on this device only.
Sweet Corn in zone 6a cities
| City | Typical last frost | Plant | Fall |
|---|---|---|---|
| Chicago, IL | Apr 11 | Apr 14 to 28 | — |
| Indianapolis city, IN | Apr 15 | Apr 15 to 29 | — |
| Denver, CO | May 4 | May 4 to 18 | — |
| Colorado Springs, CO | May 3 | May 3 to 17 | — |
| Omaha, NE | Apr 18 | Apr 18 to May 2 | — |
| Aurora, CO | May 4 | May 4 to 18 | — |
| Lincoln, NE | Apr 24 | Apr 24 to May 8 | — |
| Fort Wayne, IN | Apr 24 | Apr 24 to May 8 | — |
| Grand Rapids, MI | Apr 29 | Apr 29 to May 13 | — |
| Lakewood, CO | May 5 | May 5 to 19 | — |
| Springfield, MA | May 3 | May 3 to 17 | — |
| Joliet, IL | Apr 19 | Apr 19 to May 3 | — |
How to grow sweet cornAll zonesSweet Corn in zone 5bSweet Corn in zone 6bAbout zone 6a
Sources
- How to Grow Sweet Corn in Your Garden · Utah State University Extension
- Growing Sweet Corn in a Home Garden · University of Maryland Extension
- Growing Home Garden Sweet Corn (Circular 905) · University of Georgia Cooperative Extension
- Sweet Corn (HGIC factsheet) · Clemson Cooperative Extension Home & Garden Information Center
- Florida Vegetable Gardening Guide (SP103/VH021) · University of Florida IFAS Extension
- Vegetable Planting Calendar for Maricopa County (AZ1005) · University of Arizona Cooperative Extension
- GN 154: Soil Temperature Conditions for Vegetable Seed Germination (Harrington emergence table) · UC Cooperative Extension, Sacramento County (UC ANR)
- Fall Vegetable Gardening (SPES-801) · Virginia Cooperative Extension