One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when it's possible to plant skullcap is to refer to the USDA zone info for Granite City.

Planting Calendar for Skullcap

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

It's a bad idea to plant skullcap until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant skullcap in Granite City 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. Any later than that and your skullcap may not have a chance to really do well. Starting your skullcap indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Granite City. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Granite City is not always accurate the actual date of last frost changes from year to year. Half of the time in Granite City you get a frost after April 15 so always be ready to protect your skullcap in the event of a late frost.

USDA Zone Info for Granite City

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Granite City

You may be interested in your other planting guides for Granite City.