One of the best tools that you have as gardeners to help us figure out your 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 your area.

The USDA zone info for Bloomington should be read to figure out when you can plant welsh onion.

Planting Calendar for Welsh onion

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

Since welsh onion do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant welsh onion in Bloomington 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 welsh onion and expect a good harvest is probably August. Any later than that and your welsh onion may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your welsh onion indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Bloomington. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Bloomington may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Bloomington you get a frost after April 15 so be sure to be ready to cover your welsh onion in the event of a surprise late frost.

USDA Zone Info for Bloomington

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 Bloomington

You may be interested in your other planting guides for Bloomington.