When to Plant Blue Throatwort in Portsmouth, NH

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 Portsmouth should be reviewed to figure out when to plant blue throatwort.


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 are not cold tolerant it is necessary to wait until after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant blue throatwort
Possibly ok, but a risky time to plant blue throatwort
Probably not a good time to plant blue throatwort

The earliest that you can plant blue throatwort in Portsmouth 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 really do well. You can get started a little bit earlier by starting your blue throatwort indoors.

Last Frost Date

The average date of last frost is April 15 in Portsmouth. You can expect an average low temperature of -10°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Portsmouth and it changes from year to year. Half of the time in Portsmouth last frost occurs after April 15 so make sure that you are prepared to protect your blue throatwort if you have a surprise late frost.

USDA Zone Info for Portsmouth

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 Portsmouth

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