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

You will be able to estimate when you can plant radishes by referring to the USDA zone info for Charleston.

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 one of those plants that can tolerate quite a bit of cold weather you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant radishes in Charleston 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. You probably don't want to wait any later than that or else your radishes may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your radishes indoors.

Last Frost Date

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

Since the USDA zone info for Charleston is an average the actual date of last frost changes from year to year. Half of the time in Charleston there is a last frost after February 15 so make sure that you are ready to cover your radishes in the event of one of those late frosts.

USDA Zone Info for Charleston

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 Charleston

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