When to plant green beans in zone 4a
In zone 4a, where the last spring frost typically comes around May 13, sow outdoors June 2 to 16.
The zone 4a schedule for green beans
- Sow outdoors
- June 2 to 16
- Soil warm enough (60°F), about
- June 2
- Safest planting date (10% frost risk)
- May 27
- First harvest, roughly
- July 22 to August 25
From the median frost dates of the NOAA stations assigned to the 739 ZIP codes in zone 4a, and the timing recommended by Cooperative Extension guides for green beans.
Frost risk in zone 4a
Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 4a, the typical last frost ranges from about May 6 in the earliest tenth of ZIP codes to May 24 in the latest tenth, and the first fall frost from September 20 to October 3. For a typical place in the zone:
- April 30Risky: a later frost happens in 9 years out of 10
- May 13Typical: frost after this date in half of years
- May 27Safe: a later frost only 1 year in 10
Green Beans 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 green beans
Set your ZIP code at the top of the page and we will work out when to plant green beans where you live, from the frost records of the nearest NOAA weather station. Your ZIP code is remembered on this device only.
Green Beans in zone 4a cities
| City | Typical last frost | Plant | Fall |
|---|---|---|---|
| Fargo, ND | May 10 | May 25 to Jun 8 | — |
| Bismarck, ND | May 14 | May 28 to Jun 11 | — |
| Grand Forks, ND | May 10 | May 29 to Jun 12 | — |
How to grow green beansAll zonesGreen Beans in zone 3bGreen Beans in zone 4bAbout zone 4a
Sources
- How to Grow Beans in Your Garden · Utah State University Extension
- Growing Beans in a Home Garden · University of Maryland Extension
- Florida Vegetable Gardening Guide (SP103/VH021) · University of Florida IFAS Extension
- Vegetable Planting Calendar for Maricopa County (AZ1005) · University of Arizona Cooperative Extension
- Home Garden Beans (HGV-8) · University of Hawaii CTAHR
- GN 154: Soil Temperature Conditions for Vegetable Seed Germination (Harrington emergence table) · UC Cooperative Extension, Sacramento County (UC ANR)
- The Fall Vegetable Garden (HO-66-W) · Purdue University Extension
- Fall Vegetable Gardening (SPES-801) · Virginia Cooperative Extension
- Vegetable Gardening in Containers · Texas A&M AgriLife Extension
- Growing Vegetables in Containers · University of Wisconsin-Madison Extension