The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Oklahoma City you can estimate when you can plant zinnia by looking at the USDA zone info.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since zinnia require warm weather it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant zinnia 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 zinnia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your zinnia may not have a chance to really do well. If you are starting your zinnia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Oklahoma City the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Oklahoma City is just an average the actual date of last frost changes from year to year. Since half of the time in Oklahoma City there is a last frost after April 15 be ready to protect your zinnia in the event of one of those late frosts.

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.