Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's possible to plant welsh onion by checking out the USDA zone info for Zimmerman.

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 are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant welsh onion in Zimmerman 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. If you wait any later than that and your welsh onion may not have a chance to really do well. Starting your welsh onion indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Zimmerman. You should expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Zimmerman is just an average the actual date of last frost changes from year to year. Since half of the time in Zimmerman there is a last frost after May 15 be ready to cover your welsh onion in the event of a late frost.

USDA Zone Info for Zimmerman

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 Zimmerman

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