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.

The USDA zone info for Ventura can be reffered to in order to determine when it's the best time to plant cosmos.

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.

Since cosmos are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant cosmos in Ventura 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. You probably don't want to wait any later than that or else your cosmos may not have a chance to fully mature. If you are starting your cosmos indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Ventura the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Ventura is an average the actual date of last frost will vary from year to year. Since half of the time in Ventura last frost occurs after January 31 be ready to cover your cosmos if you have a late frost.

USDA Zone Info for Ventura

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Ventura

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