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

By looking at the USDA zone info for Sonoma you should be able to determine when you can plant streptocarpella.

Planting Calendar for Streptocarpella

Frost tolerance for streptocarpella:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since streptocarpella do not do well in cold weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant streptocarpella in Sonoma 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 streptocarpella and expect a good harvest is probably September. Any later than that and your streptocarpella may not have a chance to fully mature. Starting your streptocarpella indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Sonoma. You should expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that USDA zone info for Sonoma is just an average and the actual date of last frost changes from year to year. Half of the time in Sonoma it frosts late in the year after February 15 so make sure that you are ready to cover your streptocarpella if you have a surprise late frost.

USDA Zone Info for Sonoma

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 Sonoma

You may be interested in your other planting guides for Sonoma.