One of the first steps you take when you are figuring out 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 USDA zone info for Duncan should be used to figure out when it's possible 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.

Since blue throatwort do not do well in cold weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant blue throatwort in Duncan 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. You probably don't want to wait any later than that or else your blue throatwort may not have a chance to really do well. Starting your blue throatwort indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Duncan the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Duncan and it will vary from year to year. Half of the time in Duncan you get a frost after April 15 so make sure that you are ready to cover your blue throatwort if you have a late frost.

USDA Zone Info for Duncan

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Duncan

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