When to Plant Cosmos in Los Banos, CA

The USDA Zone info is a great tool for gardeners to help us figure out 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.

A way of making a decision about when it's the best time to plant cosmos is to check out the USDA zone info for Los Banos.


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 well in mild cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

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 Los Banos 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. If you are starting your cosmos indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Los Banos. You should expect an average low temperature of 20°F in the coldest months of winter.

Remember that USDA zone info for Los Banos is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Los Banos it frosts late in the year after February 15 so just be sure to be ready to cover your cosmos in the event of a surprise late frost.

USDA Zone Info for Los Banos

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low20°F
Highest Expected Low25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Los Banos

You may be interested in your other planting guides for Los Banos.