When can I plant Runner beans in Zone 3b

Before planting it is a good idea to find our USDA Zone info to determine our garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

The first opportunity to plant runner beans in Zone 3b should be determined by using the USDA zone info.


Planting Calendar for Runner beans

Frost tolerance for runner beans: Not tolerant of frost.
When you should plant them: After the last frost when the weather gets warmer.

Runner beans are not cold tolerant which tells us that it's important to wait until it warms up after the last frost before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant runner beans
Possibly ok, but a risky time to plant runner beans
Probably not a good time to plant runner beans

The earliest that you can plant runner beans in Zone 3b is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant runner beans and expect a good harvest is probably August. Any later than that and your runner beans may not have a chance to grow to maturity. If you are starting your runner beans indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Zone 3b the average date of last frost happens on May 15. In the coldest months of winter we should expect an average low temperature of -35°F.

Since the USDA zone info for Zone 3b may not be accurate from year to year our actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 3b there is a last frost after May 15 be ready to cover your runner beans if we have a late frost.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in our other planting guides for Zone 3b.