One of the first steps you take when you are estimating your gardening schedule is find your 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.

By referring to the USDA zone info for Astoria you will be able to figure out when you can plant polygonums.

Planting Calendar for Polygonums

Frost tolerance for polygonums:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since polygonums are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant polygonums in Astoria 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 fully mature. You can get started a couple of weeks earlier by starting your polygonums indoors.

Last Frost Date

In Astoria the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Astoria is not always accurate the actual date of last frost changes from year to year. Half of the time in Astoria you get surprised by a frost after March 15 so be sure to be ready to protect your polygonums in the event of a surprise late frost.

USDA Zone Info for Astoria

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 Astoria

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