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.

In Springfield you can estimate when to plant four o' clock by looking at 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 when the weather gets warmer.

You really shouldn't plant four o' clock until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant four o' clock in Springfield 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 fully mature. You can get started a couple of weeks earlier by starting your four o' clock indoors.

Last Frost Date

In Springfield the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Springfield is an average the actual date of last frost will vary from year to year. Since half of the time in Springfield there is a last frost after April 15 be ready to protect your four o' clock in the event of a surprise late frost.

USDA Zone Info for Springfield

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 Springfield

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