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

The USDA zone info for Sonora can be reviewed to estimate when you can plant radishes.

Planting Calendar for Radishes

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

Radishes are one of those plants that can tolerate quite a bit of cold weather which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant radishes in Sonora 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 really do well. You can get started a few weeks earlier by starting your radishes indoors.

Last Frost Date

In Sonora the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Sonora and it changes from year to year. Since half of the time in Sonora you get a frost after February 15 be ready to cover your radishes in the event of a surprise late frost.

USDA Zone Info for Sonora

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 Low	20°F
Highest Expected Low	25°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 Sonora

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