One of the best tools that you have as gardeners to help us determine 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.

It's possible to figure out when to plant astilbe by checking out the USDA zone info for Mattoon.

Planting Calendar for Astilbe

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

Astilbe can survive in a tiny bit of cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant astilbe 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 astilbe and expect a good harvest is probably August. If you wait any later than that and your astilbe may not have a chance to really do well. You can get started a couple of weeks earlier by starting your astilbe indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Mattoon and it will vary from year to year. Since half of the time in Mattoon there is a last frost after April 15 be ready to protect your astilbe if you have 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.