Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of determining when you can plant liatris is to use the USDA zone info for Sunnyvale.

Planting Calendar for Liatris

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

Liatris do well in pretty solid cold which tells us that you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant liatris in Sunnyvale 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. Any later than that and your liatris may not have a chance to fully mature. If you are starting your liatris indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Sunnyvale and it is different every year. Half of the time in Sunnyvale it frosts late in the year after February 15 so just be sure to be ready to protect your liatris in the event of one of those late frosts.

USDA Zone Info for Sunnyvale

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 Sunnyvale

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