One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant four o' clock in Alton can be estimated 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 all chance of frost has passed.

Since four o' clock are not cold tolerant it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant four o' clock in Alton 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

On average the last frost is on April 15 in Alton. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Alton is just an average and the actual date of last frost is different every year. Half of the time in Alton you get a frost after April 15 so be sure to be ready to cover your four o' clock in the event of one of those late frosts.

USDA Zone Info for Alton

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 Alton

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