Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's a good idea to plant four-o-clock flower in Carterville by checking out the USDA zone info.

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 has passed.

It's not a good idea to plant four-o-clock flower until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant four-o-clock flower in Carterville 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. If you wait any later than that and your four-o-clock flower may not have a chance to grow to maturity. If you are starting your four-o-clock flower indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Carterville. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Carterville may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Carterville it frosts late in the year after April 15 so make sure that you are ready to cover your four-o-clock flower in the event of a surprise late frost.

USDA Zone Info for Carterville

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 Carterville

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