When to Plant Dahlias in Belvidere, IL

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

The best time to plant dahlias in Belvidere can be determined by referring to the USDA zone info.


Planting Calendar for Dahlias

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

It's not a good idea to plant dahlias until after the last frost because they do not do well in cold weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant dahlias
Possibly ok, but a risky time to plant dahlias
Probably not a good time to plant dahlias

The earliest that you can plant dahlias in Belvidere 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. Starting your dahlias indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Belvidere. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Belvidere is an average the actual date of last frost is different every year. Since half of the time in Belvidere you get a frost after April 15 be ready to protect your dahlias in the event of one of those late frosts.

USDA Zone Info for Belvidere

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 Belvidere

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