When can I plant Pearl onions in Zone 4a

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.

It's a good idea to figure out when it's a good idea to plant pearl onions by using the USDA zone info for Zone 4a.


Planting Calendar for Pearl onions

Frost tolerance for pearl onions: Tolerant of a very small amount of frost.
When you should plant them: Up to 3 weeks before last frost.

Pearl onions do well in mild cold which means that you can plant them a bit earlier in the year than other frost tender plants.

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

The earliest that you can plant pearl onions in Zone 4a is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant pearl onions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your pearl onions may not have a chance to fully mature. If you are starting your pearl onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4a. In the coldest months of winter we can expect an average low temperature of -30°F.

Just be sure to remember that USDA zone info for Zone 4a is not always accurate and our actual date of last frost will vary from year to year. Half of the time in Zone 4a we get surprised by a frost after May 15 so always be ready to cover your pearl onions in the event of a late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in our other planting guides for Zone 4a.