A well-designed garden provides interest from early spring through late autumn, and beyond if you also select plants for winter structure. But, for the main growing season, much of that interest comes from flowering and foliage plants. Gardeners who want a lower maintenance landscape would be wise to look for perennial plants that are both easy-to-grow and offer a long blooming period. Most perennial plants flower for two to four weeks, but the longest flowering perennials, like coneflowers and catmint, measure their flowering period in months, not weeks. Below you’ll discover ten outstanding options for long-blooming perennials.

Why you should grow the longest flowering perennials

When planning a garden with long-blooming perennials, choose a mixture of early, mid-season, and late-flowering plants. This means a non-stop supply of nectar and pollen for bees, butterflies, and other types of pollinators, as well as plenty of flowers for cutting. It’s an easy way to create a colorful garden and there is no lack of plant choices. You’ll find a range of the longest flowering perennials at garden centres with varied flower colors and shapes and plant heights and forms.

Another way to impact bloom time and the length of the flowering period is with pruning practices like pinching, deadheading, and shearing. Combining these pruning techniques with the longest flowering perennials like catmint and coneflowers means beautiful flowers for months and months!

10 of the longest flowering perennials

Below you’ll discover ten of my favorite perennials that bloom for an extra long time.

Early blooming options for the longest flowering perennials

Light up the spring garden with these beautiful early bloomers. Not only are they colorful, but they also attract and support early bee species.

Catmint ‘Walker’s Low’ (Nepeta racemosa ‘Walker’s Low’, zones 3 to 9).

With its relaxed, trouble-free growth habit, ‘Walker’s Low’ catmint is a perfect fit for a cottage garden or rock garden, or the front edge of a perennial border or rose garden. Plus, the plants bloom their heads off from late spring until mid-autumn with a heavy show of purple-blue flower spikes that are extremely attractive to pollinators and beneficial insects. It’s no wonder this drought-tolerant, hardy plant was chosen as a Perennial Plant of the Year by the Perennial Plant Association.

As for pruning, once the initial flush of flowers begins to fade in early summer, give the plant a haircut by shearing it back by about one-half. Without a trim, the plant will continue to flower moderately, but a good shearing encourages tidy foliage and plenty of blooms that persist until frost.

Geranium ‘Rozanne’ (Geranium x ‘Rozanne’, zones 4 to 9)

I don’t like to throw the term ‘low-maintenance’ around irresponsibility, but with ‘Rozanne’, it’s the perfect description. This hardy plant forms 12 to 18 inch tall mounds of spreading foliage, which is topped from early summer until frost with two-inch wide, violet-blue flowers. After its initial bloom, the plants will continue to pump out a modest amount of fresh flowers for months. However, as with catmint, if you shear the plants back, in this case by one-third after the first blossoms fade, you’ll encourage another heavy show of flowers.

Meet more long-flowering perennials in this video:

Bleeding Heart ‘Luxuriant’ (Dicentra formosa ‘Luxuriant’, zones 2 to 9)

Long-blooming perennials for shady spaces are hard to come by, but this is where ‘Luxuriant’ shines! Growing just knee-high, this hardy selection produces clusters of reddish-pink, heart-shaped blooms throughout late spring and summer. The ferny foliage is also attractive, and makes a nice foil for the old-fashioned flowers. Plant this shade-tolerant perennial in a woodland garden, shady border, or along a tree-lined pathway. Clipping out faded flowers will promote months of bloom.

Pruning Tip – For many perennials, don’t be afraid to grab pruning shears once the initial bloom of spring flowers starts to wind down. Plants, like Geranium ‘Rozanne’, catmint cultivars, and pansies, will continue to produce flowers all season, but in a lesser quantity. If you want a heavier bloom, shear the plants back by one-third to one-half to push out fresh foliage and flowers.

Mid-season options for the longest flowering perennials

Once the early flowering perennials have finished, these beautiful bloomers continue the show into late summer.

Ornamental Onion ‘Millenium’ (Allium ‘Millenium’, zones 5 to 9)

The 2018 Perennial Plant of the Year, ‘Millenium’ is a showy selection with grassy foliage and two-inch diameter, rounded flower clusters in a bold shade of lavender-purple. The flowers bloom for around six weeks each summer, attracting every bee, butterfly, and beneficial insect for miles around. The 12 to 16 inch tall clumps are perfect for the front of a perennial border or a rock garden where the ball-shaped blooms can be appreciated. Technically a bulb, this plant is usually sold as a potted perennial and can be planted in spring or fall. Unlike many perennials, pruning doesn’t produce more flowers. To get more, divide the plants in spring or autumn.

Coneflower ‘White Swan’ and ‘Magnus’ (Echinacea purpurea, zones 3 to 9)

Coneflowers are the cornerstone of a summer perennial garden, blooming for months, even in dry, hot conditions, and providing food for butterflies, bees, and other pollinators. There are countless cultivars available to gardeners, but for months of flowers, it’s hard to beat old school selections like ‘Magnus’ and ‘White Swan’. ‘Magnus’ is a classic purple-flowering coneflower, while ’White Swan’ has large blooms with white petals and orange-copper cones. Both flower from early summer into mid-autumn, especially when deadheaded regularly. I use hand pruners to clip the flowers as they fade, which encourages lots of new buds to form.

Coreopsis ‘Full Moon’ (Coreopsis x ‘Full Moon’, zones 5 to 9)

This eye-catching plant is among the longest flowering perennials with a season that stretches from early summer to early autumn. ‘Full Moon’ is also the first introduction in the ‘Big Bang’ series of coreopsis, boasting large, soft yellow flowers that grow up to three-inches across. It also has excellent drought tolerance and is popular with the pollinators. ‘Moonbeam’ is another long-flowering coreopsis with pale yellow blooms that are smaller, but no less plentiful than those of ‘Full Moon’. I also grow ‘Heliot’ coreopsis. This cultivar has large gold and burgundy blooms that are pretty when paired with Shasta daisies or coneflowers. With all three cultivars, deadhead the flowers as they fade to encourage new buds.

Astilbe (Astilbe species, zones 4 to 9)

Astilbe stands out among the longest flowering perennials. Besides being super easy to grow, they thrive in both sunny and shaded gardens, and have feathery flowers that offers months of graceful color. And speaking of color, the blooms can be white, lavender, purple, bubblegum, deep pink, apricot, or red, often with bronze or purple foliage as well. The plants form tidy clumps with the flower plumes emerging in early to mid summer and persisting into winter. The plants do appreciate ample moisture and regular watering in dry summers can prolong the blooming period. Outstanding cultivars include ‘Bridal Veil’, ‘Pumila’, and ‘Fanal’.

Yarrow (Achillea millefolium, zones 3 to 9)

A butterfly favorite, yarrow is a robust summer bloomer with pretty, flat-topped flowers that bloom for 6 to 8 weeks. The ferny foliage emerges in early spring and is followed by the two to four-foot tall flower stems in early summer. Yarrow is one of the longest flowering perennials and grows best in full sun with well-drained soil of average fertility. Very rich soil or over-fertilizing can cause the stems to flop over. Flower colours can range from soft pastels to rich jewel shades, as well as classic gold. Deadhead spent flowers by clipping the flower stem back to the main foliage. Top yarrows to plant include ‘Moonshine’, which has pale, yellow flowers and ‘Cerise Queen’, a bright cherry-red bee magnet.

Pruning Tip – As summer flowers fade from your perennial plants, deadhead often, cutting down to a fresh stem or set of leaves. This will push the plants to continue producing more blooms. Small flowered perennials, like ‘Moonbeam’ Coreopsis, can be quickly and easily deadheaded with hedge shears, rather than snipping individual blossoms. In late summer, as flowering winds down, stop deadheading to allow some blooms to go to seed. Seedheads provide valuable food for birds and add interest to the winter garden.

Late blooming options for the longest flowering perennials

It’s amazing how many late flowering perennials are available from garden centres. You’ll find a range of plant heights, as well as flower colors and shapes. Here are some of our favorites:

Black-eyed Susan ‘Goldsturm’ (Rudbeckia fulgida ‘Goldsturm’, zones 3 to 9)

Widely considered to be among the best perennials of all time, ’Goldstrum’ lights up the garden with its bold blooms beginning in July and persisting into October. Each coneflower-shaped blossom has a raised chocolate-brown center cone surrounded by golden petals. The drought-tolerant plants grow about two-feet tall and offer the best visual effect when planted en masse. Pair them with coneflowers, bee balm, summer phlox, or ornamental grasses. Deadhead the faded flowers to prolong the bloom period.

Purple Flame Grass (Miscanthus sinensis ‘Purpurascens’, zones 3 to 9)

Maiden grasses add striking form and texture to the perennial border all summer. By late summer, many cultivars produce soft, feathery plumes that emerge above the narrow foliage. Purple flame grass is a medium-sized maiden grass, growing three to four-feet tall with foliage that turns from bright green to fiery reddish-orange in early autumn. The attractive plumes are silvery-white and persist on the plants throughout winter. Plant it in a sunny site with well-drained soil. Pruning is only necessary in early spring when the dried foliage and flower stems from the previous season are cut back before the fresh growth emerges.

Pruning Tip – In late spring, pinch out the tips of late summer and fall blooming perennials like sneezeweed, Joe Pye weed, Russian sage, and Sedum ‘Autumn Joy’. Pinching slows flowering and produces bushier growth, which means more flower-bearing stems.

For more info on growing great plants, check out the following articles: 

• Rudbeckias Powerhouse Plants
• 24 Perennials with Purple Flowers
• Learn How to Start Perennial Seeds by Winter Sowing 
• Early-blooming Perennials: 10 Favorites
• The Best Plants for Beneficial Insects

What are the longest flowering perennials growing in your garden?