The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Petaluma can be reviewed to estimate when you can plant sweet potatos.

Planting Calendar for Sweet Potatos

Frost tolerance for sweet potatos:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since sweet potatos do not do well in cold weather you need to wait until after the last frost before you can plant them.

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

Last Frost Date

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

Since the USDA zone info for Petaluma is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Petaluma last frost occurs after February 15 be ready to protect your sweet potatos in the event of 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.