The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In South Houston you can estimate when to plant nigella by referring to 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.

You can plant nigella much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant nigella in South Houston is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant nigella and expect a good harvest is probably October. You probably don't want to wait any later than that or else your nigella may not have a chance to grow to maturity. If you are starting your nigella indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In South Houston the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

It's important to remember that USDA zone info for South Houston is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in South Houston you get a frost after February 15 be ready to cover your nigella if you have a surprise late frost.

USDA Zone Info for South Houston

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in South Houston

You may be interested in your other planting guides for South Houston.