When to Plant Onions in Mascoutah, IL

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to determine when to plant onions by using the USDA zone info for Mascoutah.


Planting Calendar for Onions

Frost tolerance for onions: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Onions do well in a bit of cold which means that you can plant them quite a bit earlier in the year than other frost tender plants.

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

The earliest that you can plant onions in Mascoutah 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 onions and expect a good harvest is probably September. You probably don't want to wait any later than that or else your onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your onions indoors.

Last Frost Date

The average date of last frost is April 15 in Mascoutah. In the coldest months of winter you can expect an average low temperature of 5°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Mascoutah and it is different every year. Half of the time in Mascoutah you get surprised by a frost after April 15 so just be sure to be ready to cover your onions if you have a surprise late frost.

USDA Zone Info for Mascoutah

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low5°F
Highest Expected Low10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Mascoutah

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