One of the first steps you take when you are making a decision about 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.

You will be able to figure out when it's possible to plant skullcap by looking at the USDA zone info for Harrisburg.

Planting Calendar for Skullcap

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

Skullcap are not cold tolerant which tells us that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant skullcap in Harrisburg 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. You probably don't want to wait any later than that or else your skullcap may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your skullcap indoors.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

It's important to remember that USDA zone info for Harrisburg is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Harrisburg there is a last frost after April 15 be ready to cover your skullcap if you have a late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Harrisburg

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