One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

The USDA zone info for Clarks Summit should be used to figure out when it's a good idea to plant nigella.

Planting Calendar for Nigella

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

Nigella can survive in quite a bit of cold which tells us that you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant nigella in Clarks Summit 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. You probably don't want to wait any later than that or else 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 little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Clarks Summit. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Clarks Summit is an average and the actual date of last frost changes from year to year. Since half of the time in Clarks Summit you get a frost after April 15 be ready to protect your nigella in the event of one of those late frosts.

USDA Zone Info for Clarks Summit

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 Clarks Summit

You may be interested in your other planting guides for Clarks Summit.