When can I plant Welsh onion in Zone 1a

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 estimate when it's the best time to plant welsh onion by using the USDA zone info for Zone 1a.


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.

Since welsh onion do ok in moderate cold you can plant them just a tiny bit earlier in the year than more sensitive plants.

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 1a is June. However, you really should wait until July 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 July. You probably don't want to wait any later than that or else your welsh onion may not have a chance to grow to maturity. Starting your welsh onion indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on June 15 in Zone 1a. It might get as low as -60°F during the coldest months of winter.

Since the USDA zone info for Zone 1a is just an average our actual date of last frost can change quite a bit from year to year. Half of the time in Zone 1a it frosts late in the year after June 15 so be sure to be ready to protect your welsh onion in the event of a surprise late frost.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-60°F
Highest Expected Low-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in our other planting guides for Zone 1a.