One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant chrysocephalum in Sonoma can be figured out by reviewing the USDA zone info.

Planting Calendar for Chrysocephalum

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

Since chrysocephalum require warm weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant chrysocephalum 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 chrysocephalum and expect a good harvest is probably September. If you wait any later than that and your chrysocephalum may not have a chance to really do well. Starting your chrysocephalum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Sonoma the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Sonoma is an average the actual date of last frost changes from year to year. Since half of the time in Sonoma last frost occurs after February 15 be ready to cover your chrysocephalum in the event of 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.