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

The earliest that you can plant skullcap in Iowa Falls can be determined by using the USDA zone info.

Planting Calendar for Skullcap

Frost tolerance for skullcap:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since skullcap do not do well in cold weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant skullcap in Iowa Falls 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 couple of weeks earlier by starting your skullcap indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Iowa Falls. In the coldest months of winter you can expect an average low temperature of -20°F.

Just be sure to remember that USDA zone info for Iowa Falls is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Iowa Falls it frosts late in the year after April 15 be ready to protect your skullcap if you have a surprise late frost.

USDA Zone Info for Iowa Falls

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Iowa Falls

You may be interested in your other planting guides for Iowa Falls.