The USDA Zone info is a great tool for gardeners to help us estimate 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.

The USDA zone info for Petaluma can be reffered to in order to determine when you can plant coral bells.

Planting Calendar for Coral Bells

Frost tolerance for coral bells:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since coral bells are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant coral bells in Petaluma is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant coral bells and expect a good harvest is probably October. You probably don't want to wait any later than that or else your coral bells may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your coral bells indoors.

Last Frost Date

The average date of last frost is February 15 in Petaluma. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Petaluma is just an average the actual date of last frost changes from year to year. Half of the time in Petaluma it frosts late in the year after February 15 so be sure to be ready to protect your coral bells in the event of a surprise late frost.

USDA Zone Info for Petaluma

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Petaluma

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