One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant nigella in Altus can be determined by using 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.

Since nigella are very cold tolerant you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant nigella in Altus 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 grow to maturity. 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 Altus. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Altus may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Altus there is a last frost after April 15 so make sure that you are prepared to protect your nigella if you have one of those late frosts.

USDA Zone Info for Altus

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Altus

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