One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant blue throatwort in Pasadena can be determined by referring to the USDA zone info.

Planting Calendar for Blue Throatwort

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

It's a bad idea to plant blue throatwort until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant blue throatwort in Pasadena 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. Starting your blue throatwort indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Pasadena. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Pasadena is an average the actual date of last frost is different every year. Half of the time in Pasadena last frost occurs after February 15 so be sure to be ready to cover your blue throatwort if you have a surprise late frost.

USDA Zone Info for Pasadena

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Pasadena

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