When to Plant Zinnia in Powell, WY

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when you can plant zinnia in Powell by checking out the USDA zone info.


Planting Calendar for Zinnia

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

Zinnia are not cold tolerant which tells us that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant zinnia
Possibly ok, but a risky time to plant zinnia
Probably not a good time to plant zinnia

The earliest that you can plant zinnia in Powell 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 zinnia and expect a good harvest is probably August. Any later than that and your zinnia may not have a chance to fully mature. Starting your zinnia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Powell the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Powell is an average and the actual date of last frost is different every year. Half of the time in Powell you get a frost after May 15 so always be ready to cover your zinnia if you have one of those late frosts.

USDA Zone Info for Powell

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 Powell

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