Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of determining when to plant polygonums is to examine the USDA zone info for Hanford.

Planting Calendar for Polygonums

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

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

The earliest that you can plant polygonums in Hanford is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant polygonums and expect a good harvest is probably September. 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 couple of weeks earlier by starting your polygonums indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Hanford. It might get as low as 20°F during the coldest months of winter.

Always keep in mind that USDA zone info for Hanford is an average and the actual date of last frost is different every year. Since half of the time in Hanford you get a frost after February 15 be ready to cover your polygonums in the event of a surprise late frost.

USDA Zone Info for Hanford

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Hanford

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