The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Holland should be reviewed to determine when to plant skullcap.

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 require warm weather you need to wait until after all chance of frost has passed before you can plant them.

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

Last Frost Date

In Holland the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Holland is an average the actual date of last frost will vary from year to year. Since half of the time in Holland last frost occurs after April 15 be ready to protect your skullcap if you have one of those late frosts.

USDA Zone Info for Holland

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 Holland

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