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.

The best time to plant bunching onions in Baraboo should be determined by using 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.

You can plant bunching onions a bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant bunching onions in Baraboo 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 bunching onions and expect a good harvest is probably August. Any later than that and your bunching onions may not have a chance to grow to maturity. If you are starting your bunching onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on May 15 in Baraboo. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Baraboo is not always accurate the actual date of last frost changes from year to year. Since half of the time in Baraboo it frosts late in the year after May 15 be ready to cover your bunching onions in the event of a surprise late frost.

USDA Zone Info for Baraboo

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Baraboo

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