One of the best tools that you have as gardeners to help us figure out 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 earliest that you can plant blue throatwort in Plymouth should be estimated by reviewing 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.

Blue Throatwort are not cold tolerant which means that it's 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 Plymouth 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 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 Plymouth. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Plymouth is not always accurate the actual date of last frost is different every year. Since half of the time in Plymouth you get a frost after April 15 be ready to protect your blue throatwort in the event of a late frost.

USDA Zone Info for Plymouth

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 Plymouth

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