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 best time to plant skullcap in Rockford can be estimated by looking at the USDA zone info.

Planting Calendar for Skullcap

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

Since skullcap are not cold tolerant you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant skullcap in Rockford 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 really do well. Starting your skullcap indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Rockford may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Rockford you get surprised by a frost after April 15 so be sure to be ready to protect your skullcap in the event of a surprise late frost.

USDA Zone Info for Rockford

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 Rockford

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