One of the best tools that you have as gardeners to help us estimate 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.

You will be able to estimate when it's possible to plant nigella by reviewing the USDA zone info for Smithfield.

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 means that you can plant them much earlier than other plants that might not handle the cold.

The earliest that you can plant nigella in Smithfield 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 nigella and expect a good harvest is probably September. 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

On average the last frost is on March 15 in Smithfield. You can expect an average low temperature of 10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Smithfield and it changes from year to year. Half of the time in Smithfield last frost occurs after March 15 so make sure that you are ready to cover your nigella if you have a late frost.

USDA Zone Info for Smithfield

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Smithfield

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