Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Scappoose should be used to figure out when it's a good idea 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.

Since polygonums are not cold tolerant you have to wait until after the last frost before you can plant them.

The earliest that you can plant polygonums in Scappoose 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 fully mature. 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 Scappoose. In the coldest months of winter you should expect an average low temperature of 15°F.

Just be sure to remember that USDA zone info for Scappoose is an average and the actual date of last frost is different every year. Half of the time in Scappoose last frost occurs after March 15 so make sure that you are prepared to cover your polygonums in the event of a late frost.

USDA Zone Info for Scappoose

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 Scappoose

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