One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 should be able to estimate when it's the best time to plant skullcap by reviewing the USDA zone info for Lake Zurich.

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 need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant skullcap in Lake Zurich 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 grow to maturity. You can get started a little bit earlier by starting your skullcap indoors.

Last Frost Date

The average date of last frost is April 15 in Lake Zurich. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Lake Zurich is not always accurate the actual date of last frost is different every year. Since half of the time in Lake Zurich there is a last frost after April 15 be ready to protect your skullcap in the event of a late frost.

USDA Zone Info for Lake Zurich

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Lake Zurich

You may be interested in your other planting guides for Lake Zurich.