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 USDA zone info for Walnut Creek should be looked at 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.

Since blue throatwort are not cold tolerant you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant blue throatwort in Walnut Creek is March. However, you really should wait until April 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 September. 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. 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

On average the last frost when the weather gets warmer is on February 15 in Walnut Creek. In the coldest months of winter you can expect an average low temperature of 25°F.

Just be sure to remember that USDA zone info for Walnut Creek is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Walnut Creek you get surprised by a frost after February 15 so just be sure to be ready to cover your blue throatwort if you have a late frost.

USDA Zone Info for Walnut Creek

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Walnut Creek

You may be interested in your other planting guides for Walnut Creek.