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.

The USDA zone info for Calistoga can be reviewed to determine when it's possible to plant romanesco.

Planting Calendar for Romanesco

Frost tolerance for romanesco:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant romanesco a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant romanesco in Calistoga is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant romanesco and expect a good harvest is probably October. You probably don't want to wait any later than that or else your romanesco may not have a chance to really do well. You can get started a little bit earlier by starting your romanesco indoors.

Last Frost Date

The average date of last frost is February 15 in Calistoga. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Calistoga is just an average the actual date of last frost changes from year to year. Since half of the time in Calistoga you get surprised by a frost after February 15 be ready to cover your romanesco if you have a surprise late frost.

USDA Zone Info for Calistoga

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Calistoga

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