One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when you can plant purple coneflower is to examine the USDA zone info for Cotati.

Planting Calendar for Purple Coneflower

Frost tolerance for purple coneflower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant purple coneflower just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant purple coneflower in Cotati is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant purple coneflower and expect a good harvest is probably September. Any later than that and your purple coneflower may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your purple coneflower indoors.

Last Frost Date

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

Since the USDA zone info for Cotati is an average the actual date of last frost changes from year to year. Half of the time in Cotati there is a last frost after February 15 so always be ready to protect your purple coneflower in the event of one of those late frosts.

USDA Zone Info for Cotati

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 Cotati

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