One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Viroqua you will be able to determine when it's possible to plant nigella.

Planting Calendar for Nigella

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

Nigella tend to make it in quite a bit of cold which means that you can plant them much earlier in the year than more sensitive plants.

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

The last month that you can plant nigella and expect a good harvest is probably August. You probably don't want to wait any later than that or else your nigella may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your nigella indoors.

Last Frost Date

The average date of last frost is May 15 in Viroqua. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Viroqua is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Viroqua you get a frost after May 15 be ready to protect your nigella in the event of one of those late frosts.

USDA Zone Info for Viroqua

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Viroqua

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