One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when it's possible to plant skullcap by looking at the USDA zone info for Columbia.

Planting Calendar for Skullcap

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

You really shouldn't plant skullcap until after the last frost because they are not cold tolerant.

The earliest that you can plant skullcap in Columbia 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 fully mature. You can get started a couple of weeks earlier by starting your skullcap indoors.

Last Frost Date

In Columbia 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 Columbia is just an average the actual date of last frost will vary from year to year. Half of the time in Columbia you get a frost after April 15 so make sure that you are prepared to cover your skullcap in the event of one of those late frosts.

USDA Zone Info for Columbia

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 Columbia

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