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.

A common way of figuring out when it's a good idea to plant nigella is to examine the USDA zone info for Tulsa.

Planting Calendar for Nigella

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

Nigella do well in cold which means that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant nigella in Tulsa 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. Any later than that and 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

The average date of last frost is April 15 in Tulsa. In the coldest months of winter you can expect an average low temperature of 0°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Tulsa and it is different every year. Since half of the time in Tulsa last frost occurs after April 15 be ready to protect your nigella if you have a late frost.

USDA Zone Info for Tulsa

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Tulsa

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