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

The first opportunity to plant trifolium in Oklahoma City should be figured out by using the USDA zone info.

Planting Calendar for Trifolium

Frost tolerance for trifolium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Trifolium do ok in moderate cold which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant trifolium in Oklahoma City 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 trifolium and expect a good harvest is probably August. Any later than that and your trifolium may not have a chance to fully mature. You can get started a few weeks earlier by starting your trifolium indoors.

Last Frost Date

In Oklahoma City the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Oklahoma City is just an average and the actual date of last frost will vary from year to year. Since half of the time in Oklahoma City there is a last frost after April 15 be ready to cover your trifolium in the event of 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.