Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when you can plant radishes is to examine the USDA zone info for Columbia.

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 plants that are more sensitive to the cold.

The earliest that you can plant radishes in Columbia is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant radishes and expect a good harvest is probably September. If you wait any later than that and your radishes may not have a chance to fully mature. Starting your radishes indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Columbia. It might get as low as -5°F during the coldest months of winter.

Keep in mind that USDA zone info for Columbia is just an average and the actual date of last frost is different every year. Since half of the time in Columbia last frost occurs after April 15 be ready to cover your radishes if you have a late frost.

USDA Zone Info for Columbia

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Columbia

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