Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant dahlia in Wyoming can be estimated by referring to the USDA zone info.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Dahlia are not cold tolerant which means that it's necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlia in Wyoming 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 dahlia and expect a good harvest is probably August. Any later than that and your dahlia may not have a chance to grow to maturity. You can get started a little bit earlier by starting your dahlia indoors.

Last Frost Date

In Wyoming the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Wyoming and it changes from year to year. Since half of the time in Wyoming you get a frost after April 15 be ready to cover your dahlia if you have a late frost.

USDA Zone Info for Wyoming

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Wyoming

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