Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's a good idea to plant liatris is to use the USDA zone info for Vacaville.

Planting Calendar for Liatris

Frost tolerance for liatris:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Liatris do ok in quite a bit of cold which means that you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant liatris in Vacaville 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 liatris and expect a good harvest is probably October. If you wait any later than that and your liatris may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your liatris indoors.

Last Frost Date

The average date of last frost is February 15 in Vacaville. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Vacaville is an average the actual date of last frost will vary from year to year. Half of the time in Vacaville you get surprised by a frost after February 15 so always be ready to protect your liatris if you have one of those late frosts.

USDA Zone Info for Vacaville

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 Vacaville

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