One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when it's possible to plant cauliflower in Petaluma by reviewing the USDA zone info.

Planting Calendar for Cauliflower

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

Since cauliflower are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant cauliflower 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 cauliflower and expect a good harvest is probably October. Any later than that and your cauliflower may not have a chance to fully mature. You can get started a few weeks earlier by starting your cauliflower indoors.

Last Frost Date

In Petaluma the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Petaluma is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Petaluma you get a frost after February 15 so make sure that you are prepared to protect your cauliflower 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.