Answer: Oh my goodness! I don't know where to begin! There are so many possibilities for your sunny flower bed. Here are a few suggestions:
Achillea or yarrow is a superb plant for sunny hot spots.
Aconitum or Monkshood
Alchemilla or Lady's Mantle is a love it or hate it chartreuse flower with wonderful foliage.
Allium or ornamental onions
Aquilegia or Columbine is an excellent self-sowing perennial for sun or very light shade.
Asters or Michaelmas Daisies are the stars of the fall.
Belamcanda or Leopard Lily or even Blackberry Lily is a short-lived but lovely iris- lookalike.
Buddleia or Butterfly Bush is one of the most fragrant of garden plants. And it really does attract butterflies!
Campanula or Bellflower are delightful bloomers.
Caryopteris is a woody plant but it can be grown like a perennial.
?Centaurea, Bachelor Buttons, or Mountain Bluet are one and the same.
Chrysanthemums are one of the easiest of plants to grow.
Coreopsis or Butter Daisy" is a garden stalwart and long-blooming
Delphinium flowers are one of the loveliest of mid-summer tall flowers.
Echinacea (Purple Cone Flower)
Eschscholzia californica or California Poppy is an annual in my garden but a self-sowing perennial in many slightly warmer gardens.
Helenium is a superb bloomer if you keep it damp. If you don't keep it damp, it simply dies. One of the showiest of full sun perennials for the damp garden!
Hemerocallis or daylilies are stalwarts in the perennial border.
Iberis or Candytuft is an excellent rock garden plant in the full sun or light shade.
Iris and their sweet fragrance are one of the joys of early full sun perennials in the flower garden.
Lathyrus or perennial sweet pea is a good vine, ground cover or perennial border plant.
Lavander is among the most favorite of full sun perennials and belongs in every garden.
Madonna Lilies are one of the finest white lilies you can have in your garden.
Lupines are easy to grow if you give this plant exactly what it wants.
Lysimachia is good for sun or part shade.
Monarda or Beebalm is a garden backbone plant.
Nepeta or Perennial Catnip is a delightful perennial for full sun.
Paeonia or peonies are classic perennials for the sun.
Papaver, what can you say about poppies other than they are spectacular.
Scabiosa or Pincushion flowers blooms all summer if kept deadheaded. It doesnt' like clay but if you feed it - it blooms like mad.
Trollius or Globeflower are bright yellow relatives of the buttercup (but far better garden plants)
Veronica is one of the great blue flowers of the sunny perennial border and you should grow it for this reason alone.
Hope this short list gets you started on a spectacular perennial garden.
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