One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when you can plant skullcap by looking at the USDA zone info for Green Bay.

Planting Calendar for Skullcap

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

Skullcap are not cold tolerant which means that it is necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant skullcap in Green Bay 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 really do well. You can get started a little bit earlier by starting your skullcap indoors.

Last Frost Date

In Green Bay the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Green Bay is an average the actual date of last frost changes from year to year. Since half of the time in Green Bay last frost occurs after April 15 be ready to protect your skullcap if you have a surprise late frost.

USDA Zone Info for Green Bay

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Green Bay

You may be interested in your other planting guides for Green Bay.