One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant polygonums in Colville should be figured out by referring to the USDA zone info.

Planting Calendar for Polygonums

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

Polygonums require warm weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant polygonums in Colville is April. However, you really should wait until May 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. You can get started a few weeks earlier by starting your polygonums indoors.

Last Frost Date

The average date of last frost is April 15 in Colville. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Colville is an average and the actual date of last frost will vary from year to year. Since half of the time in Colville it frosts late in the year after April 15 be ready to cover your polygonums in the event of a surprise late frost.

USDA Zone Info for Colville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Colville

You may be interested in your other planting guides for Colville.