When to Plant Garden Mums in Romeoville, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of determining when it's possible to plant garden mums is to look at the USDA zone info for Romeoville.


Planting Calendar for Garden Mums

Frost tolerance for garden mums: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Garden Mums do well in moderate cold which tells us that you can plant them earlier than other frost tender plants.

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

The earliest that you can plant garden mums in Romeoville is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant garden mums and expect a good harvest is probably September. If you wait any later than that and your garden mums may not have a chance to fully mature. If you are starting your garden mums indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Romeoville. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Romeoville and it is different every year. Since half of the time in Romeoville it frosts late in the year after April 15 be ready to cover your garden mums if you have a surprise late frost.

USDA Zone Info for Romeoville

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 Romeoville

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