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.

In Worland you can determine when it's a good idea to plant dahlias by referring to the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Dahlias are not cold tolerant which tells us that it is important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant dahlias in Worland 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 fully mature. If you are starting your dahlias indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Worland the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Worland is an average the actual date of last frost changes from year to year. Half of the time in Worland last frost occurs after May 15 so always be ready to cover your dahlias if you have a surprise late frost.

USDA Zone Info for Worland

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 Worland

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