One of the best tools that you have as gardeners to help us determine 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.

You should be able to figure out when it's possible to plant nigella by referring to the USDA zone info for York.

Planting Calendar for Nigella

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

Nigella are very cold tolerant which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant nigella in York 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. Starting your nigella indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in York. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for York is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in York you get surprised by a frost after April 15 be ready to protect your nigella in the event of one of those late frosts.

USDA Zone Info for York

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in York

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