One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

A way of determining when it's a good idea to plant blue throatwort is to use the USDA zone info for Bristol.

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 means that you need 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 Bristol 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. If you wait any later than that and your blue throatwort may not have a chance to grow to maturity. Starting your blue throatwort indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Bristol. It might get as low as 0°F during the coldest months of winter.

Keep in mind that USDA zone info for Bristol may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Bristol last frost occurs after April 15 so make sure that you are ready to cover your blue throatwort if you have one of those late frosts.

USDA Zone Info for Bristol

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Bristol

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