One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when you can plant polygonums by using the USDA zone info for Lake Stevens.

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 are not cold tolerant which tells us that you must wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant polygonums in Lake Stevens 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. If you wait any later than that and your polygonums may not have a chance to grow to maturity. Starting your polygonums indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Lake Stevens. It might get as low as 15°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Lake Stevens and it changes from year to year. Since half of the time in Lake Stevens you get a frost after March 15 be ready to protect your polygonums if you have one of those late frosts.

USDA Zone Info for Lake Stevens

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Lake Stevens

You may be interested in your other planting guides for Lake Stevens.