Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant nigella in Richland should be figured out by reviewing 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 do well in cold you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant nigella in Richland 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. If you are starting your nigella indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Richland. You can expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Richland is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Richland last frost occurs after March 15 be ready to protect your nigella if you have a surprise late frost.

USDA Zone Info for Richland

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 Richland

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