When to plant sweet corn in zone 5a
In zone 5a, where the last spring frost typically comes around May 3, sow outdoors May 3 to 17.
The zone 5a schedule for sweet corn
- Sow outdoors
- May 3 to 17
- Safest planting date (10% frost risk)
- May 17
- First harvest, roughly
- July 2 to August 25
From the median frost dates of the NOAA stations assigned to the 2,200 ZIP codes in zone 5a, and the timing recommended by Cooperative Extension guides for sweet corn.
Frost risk in zone 5a
Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 5a, the typical last frost ranges from about April 27 in the earliest tenth of ZIP codes to May 21 in the latest tenth, and the first fall frost from September 25 to October 13. For a typical place in the zone:
- April 20Risky: a later frost happens in 9 years out of 10
- May 3Typical: frost after this date in half of years
- May 17Safe: 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 5a cities
| City | Typical last frost | Plant | Fall |
|---|---|---|---|
| Minneapolis, MN | Apr 23 | Apr 25 to May 9 | — |
| St. Paul, MN | Apr 23 | Apr 25 to May 9 | — |
| Anchorage, AK | May 5 | May 23 to Jun 6 | — |
| Sioux Falls, SD | May 1 | May 1 to 15 | — |
| Cedar Rapids, IA | Apr 28 | Apr 28 to May 12 | — |
| Billings, MT | May 10 | May 10 to 24 | — |
| Bloomington, MN | Apr 23 | Apr 23 to May 7 | — |
| Sioux City, IA | Apr 29 | Apr 29 to May 13 | — |
| Brooklyn Park, MN | Apr 30 | Apr 30 to May 14 | — |
| Woodbury, MN | Apr 24 | Apr 24 to May 8 | — |
| Plymouth, MN | Apr 29 | Apr 29 to May 13 | — |
| Blaine, MN | Apr 30 | Apr 30 to May 14 | — |
How to grow sweet cornAll zonesSweet Corn in zone 4bSweet Corn in zone 5bAbout zone 5a
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