One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 should be able to determine when it's a good idea to plant nigella by using the USDA zone info for Sulphur Springs.

Planting Calendar for Nigella

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

Since nigella are very cold tolerant you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant nigella in Sulphur Springs 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. If you wait any later than that and your nigella may not have a chance to fully mature. You can get started a little bit earlier by starting your nigella indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Sulphur Springs. In the coldest months of winter you can expect an average low temperature of 10°F.

Since the USDA zone info for Sulphur Springs is just an average the actual date of last frost is different every year. Half of the time in Sulphur Springs there is a last frost after March 15 so always be ready to protect your nigella in the event of a surprise late frost.

USDA Zone Info for Sulphur Springs

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 Sulphur Springs

You may be interested in your other planting guides for Sulphur Springs.