Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Berkeley can be looked at to figure out when it's possible 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.

It's a bad idea to plant blue throatwort until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant blue throatwort in Berkeley 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 fully mature. 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

The average date of last frost is April 15 in Berkeley. In the coldest months of winter you should expect an average low temperature of -15°F.

Just be sure to remember that USDA zone info for Berkeley is just an average and the actual date of last frost changes from year to year. Half of the time in Berkeley it frosts late in the year after April 15 so always be ready to cover your blue throatwort if you have one of those late frosts.

USDA Zone Info for Berkeley

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 Berkeley

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