One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant blue throatwort in South Houston should be estimated by reviewing 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 probably not a good idea to plant blue throatwort until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant blue throatwort in South Houston 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 few weeks earlier.

Last Frost Date

In South Houston the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 20°F.

Always keep in mind that USDA zone info for South Houston may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in South Houston there is a last frost after February 15 so always be ready to cover your blue throatwort if you have a late frost.

USDA Zone Info for South Houston

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 South Houston

You may be interested in your other planting guides for South Houston.