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.

The first opportunity to plant welsh onion in Duluth should be figured out by checking out the USDA zone info.

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.

Welsh onion do ok in moderate cold which means that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant welsh onion in Duluth is April. However, you really should wait until May 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. You probably don't want to wait any later than that or else your welsh onion may not have a chance to fully mature. You can get started a little bit earlier by starting your welsh onion indoors.

Last Frost Date

The average date of last frost is May 15 in Duluth. You can expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Duluth and it can change quite a bit from year to year. Half of the time in Duluth there is a last frost after May 15 so make sure that you are ready to cover your welsh onion if you have one of those late frosts.

USDA Zone Info for Duluth

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Duluth

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