When to Plant Cosmos in San Fernando, CA

One of the first steps you take when you are determining your gardening schedule is find your 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 San Fernando you can estimate when it's the best time to plant cosmos by checking out 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 tend to make it in some cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant cosmos
Possibly ok, but a risky time to plant cosmos
Probably not a good time to plant cosmos

The earliest that you can plant cosmos in San Fernando 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 really do well. Starting your cosmos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in San Fernando. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for San Fernando is just an average the actual date of last frost changes from year to year. Since half of the time in San Fernando there is a last frost after January 31 be ready to cover your cosmos in the event of one of those late frosts.

USDA Zone Info for San Fernando

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 Low30°F
Highest Expected Low35°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 Fernando

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