Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Oklahoma City should be read to determine when it's a good idea to 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.

Since blue throatwort are not cold tolerant you need to wait until after the last frost before you can plant them.

The earliest that you can plant blue throatwort in Oklahoma City is April. However, you really should wait until May 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 August. Any later than that and your blue throatwort may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your blue throatwort indoors.

Last Frost Date

The average date of last frost is April 15 in Oklahoma City. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Oklahoma City is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Oklahoma City you get a frost after April 15 so always be ready to protect your blue throatwort if you have a late frost.

USDA Zone Info for Oklahoma City

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Oklahoma City

You may be interested in your other planting guides for Oklahoma City.