One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 figuring out when it's a good idea to plant skullcap is to consult the USDA zone info for Irmo.

Planting Calendar for Skullcap

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

Since skullcap do not do well in cold weather it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant skullcap in Irmo 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 grow to maturity. If you are starting your skullcap indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Irmo. In the coldest months of winter you should expect an average low temperature of 10°F.

Keep in mind that USDA zone info for Irmo is not always accurate and the actual date of last frost changes from year to year. Half of the time in Irmo you get a frost after March 15 so just be sure to be ready to protect your skullcap in the event of one of those late frosts.

USDA Zone Info for Irmo

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Irmo

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