Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Petaluma you will be able to estimate when it's the best time to plant basil.

Planting Calendar for Basil

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

Basil require warm weather which tells us that you need to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant basil in Petaluma 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 basil and expect a good harvest is probably September. You probably don't want to wait any later than that or else your basil may not have a chance to really do well. If you are starting your basil indoors then you might be able to get away with starting them a few 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.

Remember 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 last frost occurs after February 15 be ready to protect your basil if you have a 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.