Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Zone 5b you can figure out when it's a good idea to plant bunching onions by reviewing the USDA zone info.

Planting Calendar for Bunching Onions

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

Bunching Onions tend to make it in some cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant bunching onions in Zone 5b 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 bunching onions and expect a good harvest is probably August. If you wait any later than that and your bunching onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your bunching onions indoors.

Last Frost Date

In Zone 5b the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Zone 5b and it can change quite a bit from year to year. Since half of the time in Zone 5b you get a frost after April 15 be ready to protect your bunching onions if you have one of those late frosts.

USDA Zone Info for Zone 5b

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Zone 5b

You may be interested in your other planting guides for Zone 5b.