The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of estimating when it's possible to plant radishes is to refer to the USDA zone info for Delaware.

Planting Calendar for Radishes

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

You can plant radishes quite a bit earlier in the year because they do well in cold.

The earliest that you can plant radishes in Delaware 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 grow to maturity. If you are starting your radishes indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Delaware the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Delaware may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Delaware there is a last frost after April 15 be ready to protect your radishes if you have one of those late frosts.

USDA Zone Info for Delaware

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Delaware

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