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

By checking out the USDA zone info for Sonoma you will be able to determine when you can plant regal geranium.

Planting Calendar for Regal Geranium

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

Regal Geranium are barely cold tolerant which means that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant regal geranium in Sonoma 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 regal geranium and expect a good harvest is probably September. Any later than that and your regal geranium may not have a chance to fully mature. You can get started a little bit earlier by starting your regal geranium indoors.

Last Frost Date

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

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Sonoma and it can change quite a bit from year to year. Since half of the time in Sonoma last frost occurs after February 15 be ready to protect your regal geranium in the event of one of those late frosts.

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.