One of the first steps you take when you are getting a good idea 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 radishes in Costa Mesa by referring to the USDA zone info.

Planting Calendar for Radishes

Frost tolerance for radishes:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Radishes do well in cold which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant radishes 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 radishes and expect a good harvest is probably October. If you wait any later than that and your radishes may not have a chance to fully mature. You can get started a few weeks earlier by starting your radishes indoors.

Last Frost Date

On average the last frost is on January 31 in Costa Mesa. In the coldest months of winter you can expect an average low temperature of 35°F.

Keep in mind that USDA zone info for Costa Mesa may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Costa Mesa it frosts late in the year after January 31 be ready to protect your radishes if you have a surprise late frost.

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.