One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of determining when to plant dahlias is to look at the USDA zone info for Rhinelander.

Planting Calendar for Dahlias

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

Since dahlias require warm weather you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlias in Rhinelander 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. Any later than that and your dahlias may not have a chance to really do well. You can get started a little bit earlier by starting your dahlias indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Rhinelander. You can expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Rhinelander and it can change quite a bit from year to year. Half of the time in Rhinelander it frosts late in the year after May 15 so be sure to be ready to protect your dahlias if you have a late frost.

USDA Zone Info for Rhinelander

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 Rhinelander

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