The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Calistoga it's possible to determine when it's a good idea to plant iberis.

Planting Calendar for Iberis

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

Iberis are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than more sensitive plants.

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

Last Frost Date

In Calistoga the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

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 a frost after February 15 be ready to protect your iberis in the event of 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.