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.

You can figure out when it's the best time to plant nigella in Williston by using the USDA zone info.

Planting Calendar for Nigella

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

Nigella are very cold tolerant which tells us that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant nigella in Williston 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. Any later than that and your nigella may not have a chance to fully mature. If you are starting your nigella indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Williston. In the coldest months of winter you should expect an average low temperature of -30°F.

Since the USDA zone info for Williston is just an average the actual date of last frost will vary from year to year. Half of the time in Williston you get surprised by a frost after May 15 so be sure to be ready to protect your nigella if you have one of those late frosts.

USDA Zone Info for Williston

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Williston

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