The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when to plant nigella is to check out the USDA zone info for Arnold.

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 earlier in the year than more sensitive plants.

The earliest that you can plant nigella in Arnold 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. If you wait any later than that and your nigella may not have a chance to grow to maturity. Starting your nigella indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Arnold the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

It's important to remember that USDA zone info for Arnold may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Arnold there is a last frost after April 15 be ready to protect your nigella in the event of one of those late frosts.

USDA Zone Info for Arnold

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 Arnold

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