When to Plant Onions in Wilmington, OH

One of the first steps you take when you are figuring out 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 it's possible to plant onions by looking at the USDA zone info for Wilmington.


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 cold weather which tells us that 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 Wilmington 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 really do well. Starting your onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Wilmington the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Wilmington and it is different every year. Since half of the time in Wilmington you get a frost after April 15 be ready to cover your onions in the event of a surprise late frost.

USDA Zone Info for Wilmington

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

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

Plants to Grow in Wilmington

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