One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when you can plant dahlias by using the USDA zone info for Baraboo.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost.

Since dahlias do not do well in cold weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlias in Baraboo is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant dahlias and expect a good harvest is probably August. If you wait any later than that and your dahlias may not have a chance to really do well. You can get started a few weeks earlier by starting your dahlias indoors.

Last Frost Date

The average date of last frost is May 15 in Baraboo. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Baraboo is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Baraboo you get surprised by a frost after May 15 be ready to protect your dahlias if you have one of those late frosts.

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.