Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Pierre you should be able to figure out when it's possible to 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 are not cold tolerant you really should wait until after the last frost before you can plant them.

The earliest that you can plant skullcap in Pierre is May. However, you really should wait until June 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. You probably don't want to wait any later than that or else your skullcap may not have a chance to grow to maturity. Starting your skullcap indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Pierre. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Pierre is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Pierre last frost occurs after May 15 be ready to cover your skullcap in the event of a surprise late frost.

USDA Zone Info for Pierre

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Pierre

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