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 blue throatwort in Mattoon should be estimated 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 has passed.

Blue Throatwort require warm weather which tells us that it is necessary to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant blue throatwort in Mattoon 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. You probably don't want to wait any later than that or else your blue throatwort may not have a chance to grow to maturity. If you are starting your blue throatwort indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Mattoon the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

It's important to remember that USDA zone info for Mattoon is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Mattoon you get a frost after April 15 so be sure to be ready to protect your blue throatwort in the event of a late frost.

USDA Zone Info for Mattoon

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Mattoon

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