The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Janesville you can estimate when it's the best time to plant blue throatwort by using the USDA zone info.

Planting Calendar for Blue Throatwort

Frost tolerance for blue throatwort:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since blue throatwort require warm weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant blue throatwort in Janesville 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 blue throatwort and expect a good harvest is probably August. Any later than that and your blue throatwort may not have a chance to fully mature. You can get started a few weeks earlier by starting your blue throatwort indoors.

Last Frost Date

The average date of last frost is April 15 in Janesville. You can expect an average low temperature of -20°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Janesville and it will vary from year to year. Since half of the time in Janesville you get a frost after April 15 be ready to protect your blue throatwort in the event of one of those late frosts.

USDA Zone Info for Janesville

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 Janesville

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