Long-Blooming Perennials – Color that Lasts All Season

Malva fastigata long-blooming perennial

A common question asked by a gardener shopping for perennials is, “Do you have something that blooms all summer?” I find I have to curb a sassy retort of, “Only if you plant petunias and marigolds!” Long-blooming color is important in a garden, but if you want a garden that is full of surprises with color-changing capacity, long-blooming perennials are the answer.

There is nothing wrong with adding the non-stop, static effect of annuals to a garden, but do you really want that kind of expense, let alone boredom in your garden? A better solution is to plant a core of long-blooming perennials like Corydalis. Picking a group of five or six from the following examples of long-blooming perennials and placing a large group here and there around the yard will not only furnish all-season color but will also unify and simplify the garden. Choices are varied for many of the options listed below prefer full sun and others like a shadier part of the yard. Some of the long-blooming perennials are tall, others are medium height or short, so with a little planning, your yard will overflow with color throughout the seasons. Perennials shown are in alphabetical order.

My favorite long-blooming Perennials shown are in alphabetical order:

Achillea hybrids, ‘Coronation Gold’ and ‘Moonshine’

achilellea
Plant achillea or yarrow with other full-sun perennials like Veronica ‘Sunny Border Blue’ (seen in the background of the photo above).

Hybrid achillea blooms from June through Labor Day. There are two achilleas that are hybrids and they are both sterile so they will not spread or set seeds. ‘Coronation Gold’ is bigger with golden, flat-topped flowers. The smaller achillea, ‘Moonshine’, pictured above, is more delicate-looking with lemon yellow blooms. Plant achillea or yarrow with other full-sun perennials like Veronica ‘Sunny Border Blue’, showing in the picture’s background.

Armeria or Thrift:

armeria thrift
Armeria or Thrift

Thrift blooms heavily in spring and sporadically the rest of the summer if spent blooms are removed. Armeria, with its grassy foliage and “foxy” pink or red flower balls, is a short evergreen perennial that when dead-headed keeps blooming. Hybrid thrifts are available in different sizes, flower and foliage colors. Thrift is excellent for front curbside gardens due to its salt and drought tolerance.

 

Centranthus or Red Valerian

Centranthus or Red Valerian
Centranthus or Red Valerian

Centranthus, or Red Valerian is a full-sun, long-blooming perennial that blooms from June through frost. Centranthus blooms longer in cooler summer areas so it is partial to mountain gardens. Removing the puff balls of seeds along with the top six-inches of the plant around the end of June will prevent seeding and reward the garden with a long second round of color. Centranthus blooms in both red and white flowers.

Coreopsis verticillea, ‘Zangreb’:

coreopsis-zangreb
The golden flowers on beautiful ferny foliage is ‘Zangreb’ threadleaf coreopsis.

‘Zangreb,’ like all threadleaf coreopsis,’ does not break dormancy until outside temperatures reach stable warmth. For this reason, they bloom the late shift in gardens, or mid-June through Labor Day. Their delicate looking blooms and needle-like foliage are distinct and beautiful. Coreopsis is a full sun perennial that’s shows off best on the front of a flowerbed. ‘Zangreb’ is hardier in colder climates so is the best coreopsis for western gardens.

Dianthus Hybrid, ‘First Love’

dianthus first love
Dianthus ‘First Love’

Dianthus ‘First Love’ is a hybrid that starts blooming in May. Its fascinating flower colors are mainly pastel but darken to a deep magenta mix over the summer. Should ‘First Love’s’ blooming slow down due to excessive heat or lack of water, trim the plant back to about five-inches. ‘First Love’ will soon be in bloom again having no idea it may be time to quit.

Heuchera or Coral Bells

Heuchera or Coral Bells - long-blooming perennials
Heuchera or Coral Bells

The delicate small size of Heuchera will add six-weeks or more of color to the front edge of a partial shady garden. To give Coral Bells a longer flowering period, trim its spent flowers, thin stalks to the foliage and they will start to bloom again. Heuchera has gained fame with hybridizing and its evergreen foliage is now available in shades of bronze, silver, lime and peach to name only a few.

Malva fastigata

Malva fastigata long-blooming perennial
Malva fastigata

Malva fastigata blooms from early to late summer with open funnel-shaped pale pink flowers.  Malva grows big and shrub-like, making it an excellent filler for the back row or where height is needed in a garden. Malva’s taproot is long and tough and almost impossible to transplant so allowing Malva to set seed will furnish an endless supply of these carefree shrubs.

Nepeta, ‘Walkers Low’

Nepeta, ‘Walkers Low’
Nepeta, ‘Walkers Low’

The soft blue spikes of Nepeta, ‘Walker’s Low’ adds a clean fragrant, fresh feeling to a garden all summer. With a late July shearing before the perennial is allowed to set seeds, Nepeta will bloom again from August to frost. ‘Walker’s Low’ is a full-sun, easy care, hybrid perennial that will not have time to reseed if it gets the July trim. The Hemerocallis daylily in front of the Nepeta is the long-blooming ‘Stella de Oro’. ‘Stella is a gold miniature that starts flowering in June to July, rests a while, and then resumes flowering sporadically in August and September.

Oneothera or Evening Primrose

Oneothera or Evening Primrose - long-blooming perennials
Oneothera or Evening Primrose

Evening primrose opens their fragrant, pale-yellow, tissue-thin petals every sunny afternoon from early summer into fall. The sprawling red stems hold elegant narrow leaves that cascade gracefully over edges or rock walls. Removing the curious looking seedpods from oneothera will curtail seed production and lengthen bloom time.

Rudbeckia fulgida, ‘Goldstrum’

Rudbeckia fulgida, ‘Goldstrum’ long-blooming perennials
Rudbeckia fulgida, ‘Goldstrum.’ Photo courtesy Walters Gardens

Rudbeckia ‘Goldstrum,’ better known as Black-eyed-Susan, fills a hot sunny garden with twenty-inch cone flowers from midsummer through fall leaving little time for self-seeding. Their prominent eye-catching cones are brown with a purple tinting that enhances the golden rays of this long-lasting, dependable perennial. Five or more Rudbeckia planted together creates a huge eye-catching color spot in a garden.

Salvia or Sage

Salvia or Sage - long-blooming perennials
Salvia or Sage

Salvia, or Sage, flowers early summer and will continue blooming all season if it gets one dead-heading. Cutting salvia back before it sets seeds is crucial, for once salvia starts seeding it stops blooming, knowing it has fulfilled its propagation role in life and will collapse. A dead-headed salvia will color a garden with its royal blue spikes into frost.

Scabosia or Pincushion

Scabosia or Pincushion long-blooming perennial
Scabosia or Pincushion

Scabosia flowers bloom continuously from late-spring through fall needing only an occasional snipping of a spent bloom. Pincushions are short, sun-loving perennials that bloom on sturdy single stems with blue three-inch flowers. They are prone to a short life due to their long bloom time.

Other long-blooming perennials not shown above are:

  • 1) centaurea or Montana Bluet that blooms and seeds prolifically both spring and fall. If the conditions are right will do a repeat performance again in June.
  • 2) Blue and white campanula carpaticas along with hot-colored gaillardia do not start blooming until June but continue into late September, giving four months of garden color.
  • Many late-season long-blooming perennials are not famous as self-seeders. It could be due to shorter summers that do not give them time to set seed. Wild Geraniums decorate part-shade gardens with color from May through July.  Heliopsis ‘Summer Sun’ flowers over seven weeks in cooler mountain gardens and will need a good Labor Day deadheading to curtail seed production. Perovskia or Russian Sage starts blooming mid-summer. The blue spikes of Russian Sage will hang on through several winter storms allowing frost to glisten on their handsome stems so their seeds won’t germinate until spring. Veronica blooms from June through August for three full months so gardeners can enjoy their deep blue spikes. Long-blooming Perennials can easily guarantee all the color a garden needs, spring through fall.
  • Traits of Long-Blooming Perennials

    Long-blooming perennials seem to fall into categories; the early self-seeders that require deadheading, the hybrid perennials that are sterile, or those who die young because they over extend themselves by non-stop blooming. There are other methods for extending all-season color in gardens. Some of my favorites include planting bulbs, planting perennials with excellent foliage, and planting perennials with persistent blooms. The small species, non-hybridized bulbs, like crocus, that bloom early and Daffodils are the most dependable and long-living of the bulbs.

  • Bergenia, sedums, hosta, and artemisias are a few choice perennials that have foliage as nice as any blooming flower.
  • Some perennials have blooms that persist or dry nicely where they bloomed. Helleborus is a good example, for they bloom in March and the flowers hold nicely until the weather heats up and dries them, but it takes a very close look to tell the blooms are dried flowers. Some Alpines hold on to their blooms like the short sedums.
  • Often gardeners think that annuals are the only way to keep their yards colorful, but showcasing clumps of these long performing perennials will unify and simplify any garden.

More about Nedra Secrist