One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

In Douglas you can estimate when it's possible 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.

Since nigella do well in cold you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant nigella in Douglas is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant nigella and expect a good harvest is probably August. Any later than that and your nigella may not have a chance to really do well. 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 Douglas the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Douglas and it can change quite a bit from year to year. Half of the time in Douglas last frost occurs after May 15 so just be sure to be ready to cover your nigella if you have a late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

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

Plants to Grow in Douglas

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