When can I plant Onions in Zone 6a

One of the best tools that we have as gardeners to help us estimate our 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 our area.

One way of estimating when to plant onions is to use the USDA zone info for Zone 6a.


Planting Calendar for Onions

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

You can plant onions quite a bit earlier in the year because they do well in cold.

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 Zone 6a 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 couple of weeks earlier by starting your onions indoors.

Last Frost Date

On average the last frost is on April 15 in Zone 6a. In the coldest months of winter we can expect an average low temperature of -10°F.

Remember that our actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Zone 6a and it will vary from year to year. Half of the time in Zone 6a there is a last frost after April 15 so be sure to be ready to protect your onions if we have a late frost.

USDA Zone Info for Zone 6a

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 Zone 6a

You may be interested in our other planting guides for Zone 6a.