The USDA Zone info is a great tool for gardeners to help us estimate 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.

It's a good idea to figure out when it's the best time to plant nigella by looking at the USDA zone info for Trenton.

Planting Calendar for Nigella

Frost tolerance for nigella:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Nigella tend to make it in a bit of cold which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant nigella in Trenton 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 really do well. Starting your nigella indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Trenton. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Trenton and it will vary from year to year. Half of the time in Trenton it frosts late in the year after April 15 so always be ready to cover your nigella in the event of a late frost.

USDA Zone Info for Trenton

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Trenton

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