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 should be able to estimate when to plant bleeding hearts by checking out the USDA zone info for Petaluma.

Planting Calendar for Bleeding Hearts

Frost tolerance for bleeding hearts:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since bleeding hearts are barely cold tolerant you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bleeding hearts in Petaluma 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 bleeding hearts and expect a good harvest is probably September. You probably don't want to wait any later than that or else your bleeding hearts may not have a chance to grow to maturity. Starting your bleeding hearts indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for Petaluma is just an average and the actual date of last frost changes from year to year. Half of the time in Petaluma last frost occurs after February 15 so just be sure to be ready to cover your bleeding hearts if you have 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.