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.

By using the USDA zone info for New Castle it's possible to estimate when it's a good idea to plant black radish.

Planting Calendar for Black radish

Frost tolerance for black radish:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Black radish do well in moderate cold which tells us that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant black radish in New Castle 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 black radish and expect a good harvest is probably September. Any later than that and your black radish may not have a chance to fully mature. Starting your black radish 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 New Castle. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for New Castle is not always accurate the actual date of last frost changes from year to year. Since half of the time in New Castle there is a last frost after April 15 be ready to cover your black radish if you have a late frost.

USDA Zone Info for New Castle

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 New Castle

You may be interested in your other planting guides for New Castle.