Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Keller you should be able to figure out when you can plant nigella.

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 other frost tender plants.

The earliest that you can plant nigella in Keller 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. Starting your nigella indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Keller. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Keller is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Keller you get surprised by a frost after March 15 so just be sure to be ready to protect your nigella in the event of one of those late frosts.

USDA Zone Info for Keller

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 Keller

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