One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Plymouth should be reffered to in order to estimate when it's the best time to plant blue throatwort.

Planting Calendar for Blue Throatwort

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

Blue Throatwort are not cold tolerant which tells us that you need to wait until it warms up after the last frost when the weather gets warmer 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. Any later than that and your blue throatwort may not have a chance to really do well. Starting your blue throatwort indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Plymouth. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Plymouth is just an average the actual date of last frost is different every year. Half of the time in Plymouth last frost occurs after April 15 so always be ready to cover your blue throatwort if you have one of those late frosts.

USDA Zone Info for Plymouth

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 Plymouth

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