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

By checking out the USDA zone info for Ukiah it's possible to determine 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 all chance of frost has passed.

It's not a good idea to plant polygonums until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant polygonums in Ukiah 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 grow to maturity. Starting your polygonums indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Ukiah the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 20°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Ukiah and it can change quite a bit from year to year. Since half of the time in Ukiah you get a frost after February 15 be ready to protect your polygonums if you have a late frost.

USDA Zone Info for Ukiah

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 Ukiah

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