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.

You can determine when it's a good idea to plant spinach in Costa Mesa by looking at the USDA zone info.

Planting Calendar for Spinach

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

Spinach tend to make it in some cold which tells us that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant spinach 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 spinach and expect a good harvest is probably October. Any later than that and your spinach may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your spinach indoors.

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.

Since the USDA zone info for Costa Mesa is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Costa Mesa there is a last frost after January 31 so make sure that you are ready to cover your spinach if you have 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.