When to Plant Mimulus in Casper, WY

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to estimate when to plant mimulus by looking at the USDA zone info for Casper.


Planting Calendar for Mimulus

Frost tolerance for mimulus: Not tolerant of frost.
When to plant: After the last frost has passed.

Mimulus do not do well in cold weather which means that it is necessary 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 mimulus
Possibly ok, but a risky time to plant mimulus
Probably not a good time to plant mimulus

The earliest that you can plant mimulus in Casper 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 mimulus and expect a good harvest is probably August. If you wait any later than that and your mimulus may not have a chance to fully mature. Starting your mimulus indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Casper the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Casper may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Casper you get a frost after April 15 be ready to cover your mimulus in the event of a surprise 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.