One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when you can plant iberis in Mattoon by referring to the USDA zone info.

Planting Calendar for Iberis

Frost tolerance for iberis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Iberis do ok in some cold which means that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant iberis in Mattoon is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant iberis and expect a good harvest is probably September. Any later than that and your iberis may not have a chance to really do well. You can get started a little bit earlier by starting your iberis indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Mattoon and it can change quite a bit from year to year. Half of the time in Mattoon you get surprised by a frost after April 15 so always be ready to cover your iberis in the event of one of those late frosts.

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.