Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Douglas can be read to figure out when 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.

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

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

Last Frost Date

The average date of last frost is May 15 in Douglas. In the coldest months of winter you should expect an average low temperature of -25°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Douglas and it changes from year to year. Half of the time in Douglas you get a frost after May 15 so always be ready to protect your skullcap if you have a late frost.

USDA Zone Info for Douglas

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 Douglas

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