One of the first steps you take when you are getting a good idea 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 first chance to plant nigella in Stillwater should be figured out by looking at 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 much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant nigella in Stillwater 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. If you wait any later than that and your nigella may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your nigella indoors.

Last Frost Date

In Stillwater the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Stillwater and it will vary from year to year. Since half of the time in Stillwater last frost occurs after May 15 be ready to protect your nigella in the event of a surprise late frost.

USDA Zone Info for Stillwater

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 Stillwater

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