Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant calendula by checking out the USDA zone info for Costa Mesa.

Planting Calendar for Calendula

Frost tolerance for calendula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Calendula can survive in some cold which means that 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 calendula in Costa Mesa is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant calendula and expect a good harvest is probably October. You probably don't want to wait any later than that or else your calendula may not have a chance to fully mature. If you are starting your calendula 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 January 31 in Costa Mesa. In the coldest months of winter you can expect an average low temperature of 35°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Costa Mesa and it changes from year to year. Half of the time in Costa Mesa you get a frost after January 31 so be sure to be ready to cover your calendula in the event of one of those late frosts.

USDA Zone Info for Costa Mesa

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Costa Mesa

You may be interested in your other planting guides for Costa Mesa.