A well-designed landscape or garden should showcase interesting flowers and foliage through all four seasons, with one fading bloom phase passing the baton to another peaking bloom phase. While many perennials often bloom for weeks, there are several that will give you months of blooms, and straddle two or more seasons. Here are some of the longest-blooming perennials you can use in your Seacoast garden.
Early Season
Nepeta (also known as Catmint) will bloom from late spring until mid autumn with a heavy show of purple-blue flower spikes. ‘Walker’s Low’ is a particularly popular variety and was chosen as the 2007 Perennial Plant of the Year. Once the initial flush of flowers begins to fade, give the plant a haircut, shearing it back to the fresh clump of leaves appearing at its base. This tidies the foliage and encourages a new flush of blooms that will persist until frost sets in.
Hardy Geranium (also known as Cranesbill) blooms from early summer until frost. ‘Rozanne’ is a particularly popular variety that will continue to re-bloom prolifically, especially if deadheaded regularly.
Dicentra (Also known as Bleeding Heart) is a fantastic long-blooming perennial for shady spaces, and re-blooming is encouraged by the removal of spent blooms.
Mid Season:
Allium (Also known as Ornamental Onion) bloom for around six weeks each summer. ‘Millenium’ is a very popular variety, and was the 2018 Perennial Plant Association ‘s Plant of The Year. Because of its bulbous nature, pruning does not produce more flowers.
Salvia (commonly called Meadow Sage) first blooms in spring and, if deadheaded regularly, will bloom into autumn. ‘Blue Hill,’ ‘May Night,’ ‘Rose Marvel,’ and ‘Caradonna’ are very popular varieties.
Daylily flowers only last for one day, but the plant will produce a myriad of flowers from May through July, and is encouraged by deadheading. ‘Stella de Oro’ is well liked for its particularly long bloom season.
“Repeat-blooming” or Floribunda Roses are commonly available today in many shapes and colors. Knockout Roses are bred to have extended bloom seasons running from spring through late fall. Many David Austin roses are also bred for prolonged bloom seasons.
Yarrow often blooms from June through September.
English Lavender grows from June through August, and like Russian Sage, loves full sun and arid conditions.
Butterfly bushes typically bloom from June through September.
Veronica spicata blooms from June through August and benefits from deadheading. ‘Royal Candles’ is well liked for its beauty and particularly long bloom season.
Rudbeckia (commonly called Black-eyed Susan) blooms from late June through October in most climates. Deadheading will prompt more frequent reblooming.
Echinacea (commonly called Coneflowers) typically bloom from June through August on plants that grow 2 to 5 feet in height.
Russian Sage blooms from July through October, and loves sunny, arid conditions.
Daisies make great cut flowers, and by deadheading them, you encourage re-bloom. The variety named ‘Becky’ blooms from July through September, and many other early or late varieties can help you stagger bloom periods.
Threadleaf Coreopsis is a workhorse, and will first bloom in mid to late summer, but can be stimulated into a second flush of flowers in the fall if the plants are sheared back after their initial show is done.
Late Season:
Sedums bloom in late summer and their blooms persist through autumn. Their dried flower heads retain their beauty through the winter as well. ‘Autumn Joy’ is extremely popular and highly prized for the long-lasting fall interest it provides.
Astilbe thrives in both sunny or shaded gardens, and forms tidy clumps with flower plumes emerging in early to mid summer and persisting into winter.
While technically not a flower, Ornamental or Decorative Grasses begin to awaken in spring, and look flushed out nicely by summer. In late summer, many of them are showing off decorative plumes that will persist through autumn. Their dried foliage adds wonderful winter interest in a garden as well.
Here’s a printable brochure from the Perennial Plant Association with more great information.