One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Cotati you can figure out when to plant cosmos by reviewing the USDA zone info.

Planting Calendar for Cosmos

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

Cosmos do ok in moderate cold which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant cosmos 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 cosmos and expect a good harvest is probably September. Any later than that and your cosmos may not have a chance to fully mature. You can get started a little bit earlier by starting your cosmos indoors.

Last Frost Date

In Cotati the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Cotati may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Cotati you get surprised by a frost after February 15 so always be ready to cover your cosmos 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.