The USDA Zone info is a great tool for gardeners to help us figure out 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 possible to estimate when to plant skullcap by reviewing the USDA zone info for Chicago Ridge.

Planting Calendar for Skullcap

Frost tolerance for skullcap:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Skullcap require warm weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant skullcap in Chicago Ridge is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant skullcap and expect a good harvest is probably August. If you wait any later than that and your skullcap may not have a chance to grow to maturity. If you are starting your skullcap 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 Chicago Ridge. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Chicago Ridge is just an average and the actual date of last frost will vary from year to year. Half of the time in Chicago Ridge last frost occurs after April 15 so just be sure to be ready to cover your skullcap in the event of a surprise late frost.

USDA Zone Info for Chicago Ridge

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 Chicago Ridge

You may be interested in your other planting guides for Chicago Ridge.