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.

You can estimate when you can plant polygonums in Pasadena by using the USDA zone info.

Planting Calendar for Polygonums

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

Polygonums require warm weather which means that you really should wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant polygonums in Pasadena 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 little bit earlier.

Last Frost Date

In Pasadena 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.

Since the USDA zone info for Pasadena is not always accurate the actual date of last frost changes from year to year. Half of the time in Pasadena it frosts late in the year after February 15 so make sure that you are ready to cover your polygonums in the event of one of those late frosts.

USDA Zone Info for Pasadena

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 Pasadena

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