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.

A way of figuring out when it's a good idea to plant blue throatwort is to check out the USDA zone info for Roseville.

Planting Calendar for Blue Throatwort

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

Since blue throatwort require warm weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant blue throatwort in Roseville 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. If you wait any later than that and 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 few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Roseville. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Roseville is just an average the actual date of last frost will vary from year to year. Half of the time in Roseville you get a frost after February 15 so just be sure to be ready to cover your blue throatwort if you have one of those late frosts.

USDA Zone Info for Roseville

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 Roseville

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