When to Plant Peonies in Casper, WY

One of the best tools that you have as gardeners to help us determine 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.

A way of making a decision about when you can plant peonies is to consult the USDA zone info for Casper.


Planting Calendar for Peonies

Frost tolerance for peonies: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Peonies do well in mild cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

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

The earliest that you can plant peonies in Casper is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant peonies and expect a good harvest is probably August. You probably don't want to wait any later than that or else your peonies may not have a chance to grow to maturity. If you are starting your peonies indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Casper. You can expect an average low temperature of -20°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Casper is just an average and the actual date of last frost will vary from year to year. Half of the time in Casper there is a last frost after April 15 so make sure that you are prepared to protect your peonies in the event of a late frost.

USDA Zone Info for Casper

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Casper

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