When to Plant Mimulus in Lewistown, MT

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant mimulus in Lewistown should be determined by reviewing the USDA zone info.


Planting Calendar for Mimulus

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

You really shouldn't plant mimulus until after the last frost has passed because they are not cold tolerant.

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 Lewistown 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 mimulus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your mimulus may not have a chance to really do well. If you are starting your mimulus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Lewistown the average date of last frost happens on May 15. You can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Lewistown is just an average the actual date of last frost will vary from year to year. Since half of the time in Lewistown last frost occurs after May 15 be ready to protect your mimulus if you have one of those late frosts.

USDA Zone Info for Lewistown

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Lewistown

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