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.

One way of getting a good idea when it's the best time to plant black radish is to examine the USDA zone info for Sun Prairie.

Planting Calendar for Black radish

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

You can plant black radish just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant black radish in Sun Prairie 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. You probably don't want to wait any later than that or else your black radish may not have a chance to really do well. Starting your black radish indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Sun Prairie. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Sun Prairie may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Sun Prairie there is a last frost after April 15 so make sure that you are prepared to cover your black radish if you have one of those late frosts.

USDA Zone Info for Sun Prairie

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Sun Prairie

You may be interested in your other planting guides for Sun Prairie.