The weather is not predictable for Montana and it's hard to know when it's best to plant or replant flowers outdoors. I always seem to put them outdoors too early and they are a lot harder to keep alive and I end up killing a few.

I always get so excited and want to plant on the first sunny days. That is not a good idea and best to wait till it is warm for a few consecutive days and warms up at night. MSU Extension published an article and talked about planting flowers outside in Western Montana. "For much of western Montana, seed about April 1 since the date of last frost is often close to June 1," they say. Then they talk about the difference with the eastern side and how it warms up about a month earlier: "March 15 may be a better date in much of eastern Montana" (for just seed not outside).

Most things are after frost which as you read could be close to June 1st. Pansy's and Sunflowers are a couple examples of flowers you can plant early spring.