The USDA Zone info is a great tool for gardeners to help us estimate 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 San Carlos can be looked at to estimate when 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.

Cosmos tend to make it in a tiny bit of cold which tells us that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant cosmos in San Carlos 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 grow to maturity. You can get started a few weeks earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost has passed is on January 31 in San Carlos. It might get as low as 30°F during 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 San Carlos and it is different every year. Since half of the time in San Carlos you get a frost after January 31 be ready to cover your cosmos in the event of a late frost.

USDA Zone Info for San Carlos

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 San Carlos

You may be interested in your other planting guides for San Carlos.