When to Plant Onions in Menomonee Falls, WI

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant onions in Menomonee Falls can be estimated by reviewing the USDA zone info.


Planting Calendar for Onions

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

Since onions do well in cold you can plant them a lot 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 Menomonee Falls 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. If you wait any later than that and your onions may not have a chance to grow to maturity. You can get started a little bit earlier by starting your onions indoors.

Last Frost Date

The average date of last frost is April 15 in Menomonee Falls. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Menomonee Falls may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Menomonee Falls last frost occurs after April 15 so always be ready to protect your onions if you have a late frost.

USDA Zone Info for Menomonee Falls

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 Menomonee Falls

You may be interested in your other planting guides for Menomonee Falls.