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.

In Yorkville you can determine when it's the best time to plant nigella by reviewing the USDA zone info.

Planting Calendar for Nigella

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

Nigella do well in pretty solid 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 Yorkville 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. You can get started a little bit earlier by starting your nigella indoors.

Last Frost Date

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

Since the USDA zone info for Yorkville is an average the actual date of last frost is different every year. Since half of the time in Yorkville you get a frost after April 15 be ready to cover your nigella if you have a surprise late frost.

USDA Zone Info for Yorkville

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 Yorkville

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