Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Holtville can be used to determine when it's possible to plant radishes.

Planting Calendar for Radishes

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

Since radishes are very cold tolerant you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant radishes in Holtville 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 couple of weeks earlier by starting your radishes indoors.

Last Frost Date

The average date of last frost is January 31 in Holtville. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Holtville is not always accurate the actual date of last frost changes from year to year. Half of the time in Holtville you get a frost after January 31 so always be ready to cover your radishes if you have a surprise late frost.

USDA Zone Info for Holtville

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 Low	30°F
Highest Expected Low	35°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 Holtville

You may be interested in your other planting guides for Holtville.