Summer-Blooming Perennial Flowers

Flowering perennials, such as black-eyed Susan, add color and texture to your garden.

Flowering perennials add color, texture and height to the landscape. Perennials live for several growing seasons. Generally, perennials die back to the ground in winter, then grow back in the spring. According to the Colorado State University Extension, perennials flowers usually require less maintenance and use less water than annuals. Since different perennial species bloom at different times during the growing season, with a bit of planning, your garden can feature blossoms from spring to fall.

Planning a Perennial Garden

Because perennial flowers can survive for several seasons, choose plants carefully. Group the same species of plants in clumps of three, five or seven throughout the garden, interspersing with clumps of perennials that bloom at different times for constant color. To create flow, plant taller species toward the back or middle of a bed, graduating down to shorter species at the borders. Plant groupings in triangular shapes, rather than in straight lines, to create visual interest.

Early Summer Bloomers

Peonies bloom from late spring through early summer.

Early summer perennials generally bloom from late spring until May or early June. These include basket-of-gold (Aurinia saxatilis), bellflower (Campanula carpatica), bloodroot (Sanguinaria canadensis), buglewood (Ajuga reptans), candytuft (Iberis sempervirens), columbine (Aquilegia spp.), delphinium (Delphinium x elatum), false rock cress (Abrietia deltoidea), flax (Linum spp.), Jacob's ladder (Polemonium reptans), maiden pink (Dianthus deltoides), Oriental poppy (Papaver orientalis), peony (Paeonia spp.), Persian cornflower (Centaurea dealbata), prairie smoke (Geum triflorum), sea pink (Armeria maritime), Siberian bugloss (Brunnera macrophylla), and snow-in-summer (Cerastium tomentosum).

Mid-summer Bloomers

Clematis produce flowers through the mid-summer months.

Mid-summer bloomers produce colorful blossoms from June to August. These include blanketflower (Gaillardia grandiflora), chocolate flower (Berlandiera lyrata), clematis (Clematis spp.), coreopsis (Coreopsis spp.), Cupid's dart (Catananche caeruleal), false spirea (Astilbe spp.), false sunflower (Heliopsis cvs.), fern leafed yarrow (Achillea filipendula var.), garden phlox (Phlox paniculata), gloriosa daisy (Rudbeckia x hybrida), gooseneck loosestrife (Lysmachia clethroides), hollyhock (Alcea hyb.), hyssop (Agastache cana), luxuriant bleeding heart (Dicentra eximia), moonbeam (Coreopsis verticillata), poppy mallow (Callirhoe involucrate), red valerian (Centranthus rubber), and sundrops (Oenothera fruticosa).

Late Summer Bloomers

Late summer bloomers produce blossoms from August through the warmer autumn months. These include black-eyed Susan (Rudbeckia fulgida), chrysanthemum (Deudranthuna x grandiflora), coneflower (Echinacea purpurea), coralbells (Heuchera sanguinea), dward fall aster (Aster novi-belgii), globe thistle (Echinops ritro), hardy mum (Chrysanthemum moritolum), meadow sage (Salvia superba), mullein (Verbascum spp.), obedient plant (Physostegia virginiana), pearly everlasting (Anaphelsis triplineruis), rose mallow (Hibiscus moscheutus), Shasta daisy (Leucanthemum x supermum), sneezeweed (Helenium autumnale), Stokes aster (Stokesia laevis), and stonecrop (Sedum spp.).

Extended Bloomers

Daylilies produce blooms all summer long.

Some perennials bloom over an entire growing season, from late spring until early autumn. These include balloon flower (Platycodon grandiflorus), butterfly weed (Asclepias tuberose), daylilies (Hemerocallis spp.), deadnettle (Lamium maculatum), Dyer's chamomile (Anthemis tinctoria), hollyhock (Alcea rosea), lavender (Lavendula angustifolia), Mexican daisy (Erigeron spp.), pincushion flower (Scabiosa caucasica), potentilla (Potentilla verna), Russian sage (Perovskia atriplicifolia), silver mound (Artemesia spp.), and yarrow (Achillea spp.).

References

• University of Idaho Extension: Perennials Classified by Bloom Period
• Penn State Cooperative Extension Franklin County; Long Blooming Perennials for Pennsylvania Landscapes; Steve Bogash; 2009
• Oregon State University; Extension Service Garden Hints; Carol Savonen
• Colorado State University Extension; Perennial Gardening; D. Waltman, et al.; 2009
• Colorado State University Extension; Herbaceous Perennials; M. Meehan, et al.; 2008

Resources

• Iowa State University: Thirty of the Longest Blooming Perennials