When can I plant Tree onions in Zone 1b

One of the best tools that we have as gardeners to help us figure out 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.

The earliest that you can plant tree onions in Zone 1b should be estimated by looking at the USDA zone info.


Planting Calendar for Tree onions

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

You can plant tree onions a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

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

The earliest that you can plant tree onions in Zone 1b 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 tree onions and expect a good harvest is probably July. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. Starting your tree onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is June 15 in Zone 1b. It might get as low as -55°F during the coldest months of winter.

Just be sure to remember that our actual date of last frost is just an average because it is based on the USDA zone info for Zone 1b and it is different every year. Half of the time in Zone 1b we get surprised by a frost after June 15 so make sure that you are prepared to protect your tree onions in the event of a late frost.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-55°F
Highest Expected Low-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

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