One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when you can plant four-o-clock flower by using the USDA zone info for Cincinnati.

Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Four-o-clock flower do not do well in cold weather which means that it's necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant four-o-clock flower in Cincinnati 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 four-o-clock flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your four-o-clock flower may not have a chance to grow to maturity. You can get started a little bit earlier by starting your four-o-clock flower indoors.

Last Frost Date

The average date of last frost is April 15 in Cincinnati. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for Cincinnati is just an average the actual date of last frost changes from year to year. Half of the time in Cincinnati you get a frost after April 15 so make sure that you are ready to protect your four-o-clock flower if you have a late frost.

USDA Zone Info for Cincinnati

Here is the info for USDA Zone 6b.

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

Plants to Grow in Cincinnati

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