Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when you can plant nigella by looking at the USDA zone info for Princeton.

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 earlier in the year because they are very cold tolerant.

The earliest that you can plant nigella in Princeton 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. 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 Princeton the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

It's important to remember that USDA zone info for Princeton is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Princeton there is a last frost after April 15 so always be ready to protect your nigella if you have a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Princeton

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