One of the first steps you take when you are figuring out 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.

You should be able to figure out when it's possible to plant flower-of-an-hour by using the USDA zone info for Mattoon.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Flower-of-an-Hour are barely cold tolerant which means that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant flower-of-an-hour in Mattoon is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to grow to maturity. You can get started a little bit earlier by starting your flower-of-an-hour indoors.

Last Frost Date

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

Since the USDA zone info for Mattoon is not always accurate the actual date of last frost will vary from year to year. Half of the time in Mattoon last frost occurs after April 15 so be sure to be ready to cover your flower-of-an-hour in the event of a surprise late frost.

USDA Zone Info for Mattoon

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 Mattoon

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