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 looked at to figure out when to plant heuchera.

Planting Calendar for Heuchera

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

You can plant heuchera a little earlier in the year because they do well in moderate cold.

The earliest that you can plant heuchera 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 heuchera and expect a good harvest is probably October. If you wait any later than that and your heuchera may not have a chance to fully mature. If you are starting your heuchera indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Petaluma. In the coldest months of winter you should expect an average low temperature of 25°F.

Keep in mind that USDA zone info for Petaluma is just an average and the actual date of last frost is different every year. Since half of the time in Petaluma there is a last frost after February 15 be ready to protect your heuchera if you have one of those late frosts.

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.