Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant dahlias in River Forest by reviewing the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost.

Dahlias are not cold tolerant which means that it's necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlias in River Forest 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 dahlias and expect a good harvest is probably August. Any later than that and your dahlias may not have a chance to really do well. If you are starting your dahlias indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for River Forest is not always accurate the actual date of last frost changes from year to year. Since half of the time in River Forest you get surprised by a frost after April 15 be ready to protect your dahlias if you have a late frost.

USDA Zone Info for River Forest

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 River Forest

You may be interested in your other planting guides for River Forest.