The USDA Zone info is a great tool for gardeners to help us estimate 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.

You should be able to figure out when it's possible to plant blue throatwort by looking at the USDA zone info for Grafton.

Planting Calendar for Blue Throatwort

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

It's probably not a good idea to plant blue throatwort until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant blue throatwort in Grafton 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 couple of weeks earlier.

Last Frost Date

In Grafton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Grafton and it changes from year to year. Half of the time in Grafton you get a frost after April 15 so be sure to be ready to cover your blue throatwort if you have a surprise late frost.

USDA Zone Info for Grafton

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 Grafton

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