When to Plant Dahlias in Harvey, IL

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 Harvey should be figured out 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 when the weather gets warmer.

Since dahlias are not cold tolerant you must wait until after the last frost before you can plant them.

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 Harvey 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. You probably don't want to wait any later than that or else your dahlias may not have a chance to grow to maturity. You can get started a little bit earlier by starting your dahlias indoors.

Last Frost Date

In Harvey 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 USDA zone info for Harvey is just an average and the actual date of last frost changes from year to year. Since half of the time in Harvey it frosts late in the year after April 15 be ready to protect your dahlias if you have a late frost.

USDA Zone Info for Harvey

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 Harvey

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