The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's the best time to plant four o' clock in Keokuk by referring to the USDA zone info.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant four o' clock until after the last frost because they do not do well in cold weather.

The earliest that you can plant four o' clock in Keokuk 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 and expect a good harvest is probably August. If you wait any later than that and your four o' clock may not have a chance to grow to maturity. Starting your four o' clock indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Keokuk. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Keokuk is just an average the actual date of last frost changes from year to year. Half of the time in Keokuk you get surprised by a frost after April 15 so always be ready to protect your four o' clock if you have a surprise late frost.

USDA Zone Info for Keokuk

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Keokuk

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