Before planting it is a good idea to find your USDA Zone info to determine 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.

You should be able to figure out when it's possible to plant tree onions by reviewing the USDA zone info for Prairie Du Chien.

Planting Calendar for Tree onions

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

Tree onions tend to make it in a tiny bit of cold which means that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant tree onions in Prairie Du Chien 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 Prairie Du Chien. In the coldest months of winter you can expect an average low temperature of -20°F.

Just be sure to remember that USDA zone info for Prairie Du Chien is just an average and the actual date of last frost is different every year. Half of the time in Prairie Du Chien it frosts late in the year after April 15 so just be sure to be ready to protect your tree onions if you have a late frost.

USDA Zone Info for Prairie Du Chien

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Prairie Du Chien

You may be interested in your other planting guides for Prairie Du Chien.