When can I plant Tree onions in Zone 6b

One of the first steps we take when we are determining our gardening schedule is find our USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

The first chance to plant tree onions in Zone 6b should be figured out by referring to 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.

Tree onions are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than other frost tender plants.

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 6b is March. However, you really should wait until April 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 August. Any later than that and your tree onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is April 15 in Zone 6b. In the coldest months of winter we can expect an average low temperature of -5°F.

It's important to remember that our actual date of last frost is just an average because it is based on the USDA zone info for Zone 6b and it is different every year. Since half of the time in Zone 6b last frost occurs after April 15 be ready to cover your tree onions if we have one of those late frosts.

USDA Zone Info for Zone 6b

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Zone 6b

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