When to Plant Polygonums in Zone 3b

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Zone 3b you will be able to estimate when it's the best time to plant polygonums.


Planting Calendar for Polygonums

Frost tolerance for polygonums: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

You should not plant polygonums until after the last frost because they are not cold tolerant.

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

The earliest that you can plant polygonums 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 polygonums and expect a good harvest is probably August. You probably don't want to wait any later than that or else your polygonums may not have a chance to really do well. If you are starting your polygonums indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 3b. In the coldest months of winter you can expect an average low temperature of -35°F.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Zone 3b and it is different every year. Since half of the time in Zone 3b you get a frost after May 15 be ready to cover your polygonums if you have one of those late frosts.

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 your other planting guides for Zone 3b.