One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's a good idea to plant nigella in Litchfield by referring to 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 plant them a quite a bit earlier than other plants that might not handle the cold.

The earliest that you can plant nigella in Litchfield 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. Starting your nigella indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Litchfield the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Litchfield and it can change quite a bit from year to year. Since half of the time in Litchfield it frosts late in the year after May 15 be ready to cover your nigella in the event of a surprise late frost.

USDA Zone Info for Litchfield

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 Litchfield

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