The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's possible to plant polygonums is to examine the USDA zone info for San Bruno.

Planting Calendar for Polygonums

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

It's a bad idea to plant polygonums until after the last frost because they do not do well in cold weather.

The earliest that you can plant polygonums in San Bruno is February. However, you really should wait until March 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. If you wait any later than that and your polygonums may not have a chance to really do well. Starting your polygonums indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is January 31 in San Bruno. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for San Bruno is just an average the actual date of last frost is different every year. Since half of the time in San Bruno there is a last frost after January 31 be ready to cover your polygonums if you have a surprise late frost.

USDA Zone Info for San Bruno

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in San Bruno

You may be interested in your other planting guides for San Bruno.