Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Edwardsville it's a good idea to determine when you can plant skullcap.

Planting Calendar for Skullcap

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

Since skullcap require warm weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant skullcap in Edwardsville 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 fully mature. Starting your skullcap indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Edwardsville the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Edwardsville is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Edwardsville last frost occurs after April 15 so always be ready to protect your skullcap in the event of one of those late frosts.

USDA Zone Info for Edwardsville

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 Edwardsville

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