When can I plant Welsh onion in Zone 3b

One of the best tools that we have as gardeners to help us determine our gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

You can figure out when to plant welsh onion in Zone 3b by using the USDA zone info.


Planting Calendar for Welsh onion

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

Welsh onion do well in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant welsh onion in Zone 3b 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 welsh onion and expect a good harvest is probably August. You probably don't want to wait any later than that or else your welsh onion may not have a chance to really do well. If you are starting your welsh onion indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Zone 3b. In the coldest months of winter we can expect an average low temperature of -35°F.

It's important to remember that USDA zone info for Zone 3b is not always accurate and our actual date of last frost will vary from year to year. Since half of the time in Zone 3b we get a frost after May 15 be ready to cover your welsh onion if we have a late frost.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in our other planting guides for Zone 3b.