One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant skullcap in Elmhurst should be figured out by using the USDA zone info.

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

The earliest that you can plant skullcap in Elmhurst 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 fully mature. If you are starting your skullcap indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

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

USDA Zone Info for Elmhurst

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 Elmhurst

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