The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant dahlia in River Grove can be estimated by reviewing the USDA zone info.

Planting Calendar for Dahlia

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

Dahlia do not do well in cold weather which means that it is necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant dahlia in River Grove 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 dahlia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dahlia may not have a chance to grow to maturity. Starting your dahlia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In River Grove the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for River Grove and it will vary from year to year. Half of the time in River Grove you get surprised by a frost after April 15 so make sure that you are ready to cover your dahlia if you have a late frost.

USDA Zone Info for River Grove

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in River Grove

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