roses,they go with everything.
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HYDRANGEAS! add the proper mix so you get the blue/purple shades
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How about white daisies? The yellow centers would compliment the blue roof and bring out the whiteness of the house.

You can also try yellow tulips or daffodils if you don’t like daisies. Anyhow, all three of these flowers are simple and sweet and will make your home look welcome-y.
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geraniums, lilies, black-eyed susan…iris, tulips, daffodils, zinnias, clematis….

You can do what ever you love that will grow where you live.
Take into account climate, shade, water requirements of the plants, the time you want to spend caring for them….

Then visit a garden center or search the web for information. Do you want annuals (only around for one year) or perennials, which come back year after year. How much space do you have? Do you want formal looking plants or more free style? Anything goes, as long as you love them and will care for them as they need.
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Can’t wait for spring……I’m sick of snow….

The ones with white flowers and blue roots. lol I think exotic lilies would look good.
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Lots of red. Geraniums would be great. Red roses, purple coneflower, purple petunias. Don’t do anything white or pale in color. You want lots of contrast. Dark greens, like Hostas would be good, too.
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You didn’t mention your light requirements so I can’t help you with species. But as for color, I’d go with pale yellow, sky blue and pastel peach.
Depending on your light requirements, this may include achillea (yarrow), hardy geranium, helianthemum, pulmonaria (lungwort), oenethra, coreopsis and many many others. You may want to include a few annuals with your perennials for summer-long bloom. Try browsing a plant and seed catalogue for ideas.
Always plant in clumps rather than many different individual plants. At home, I like to use what I call "anchor" plants; repeat these plantings at the ends and in the center, and fill in with different varieties. It will give your garden a pulled-together appearance. You may want to "anchor" with some lovely flowering shrubs, like viburnum, itea, hydrangea, spirea and weigela. All come in a varity of colors; again what you plant will depend on your light requirements.
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You can do several different flowers all in the same color to make it look interesting on a textural level, or you can plant all the same flower. It may seem trite, but red flowers would look great. Pink will also do well. I would steer away from white. Yellow and orange would look nice.
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