The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when it's the best time to plant blue throatwort by looking at the USDA zone info for Phoenix.

Planting Calendar for Blue Throatwort

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

You really shouldn't 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 Phoenix 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 fully mature. Starting your blue throatwort indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Phoenix the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Phoenix and it is different every year. Since half of the time in Phoenix there is a last frost after February 15 be ready to protect your blue throatwort in the event of a surprise late frost.

USDA Zone Info for Phoenix

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 Phoenix

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