Before planting it is a good idea to find your USDA Zone info to determine 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 Healdsburg can be looked at to determine when you can plant blue throatwort.

Planting Calendar for Blue Throatwort

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

It's a bad idea to plant blue throatwort until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant blue throatwort in Healdsburg 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 grow to maturity. If you are starting your blue throatwort indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Healdsburg. You should expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Healdsburg and it changes from year to year. Half of the time in Healdsburg last frost occurs after February 15 so just be sure to be ready to cover your blue throatwort in the event of a late frost.

USDA Zone Info for Healdsburg

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 Healdsburg

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