One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Sonoma you can determine when it's a good idea to plant calla lily by using the USDA zone info.

Planting Calendar for Calla Lily

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

Calla Lily require warm weather which tells us that it's necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant calla lily 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 calla lily and expect a good harvest is probably September. Any later than that and your calla lily may not have a chance to fully mature. Starting your calla lily indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Sonoma may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Sonoma you get surprised by a frost after February 15 be ready to protect your calla lily 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.