The traditional tradeoff for buying perennial flowers – the ones that come back year after year – is that they have a limited bloom time.
Unlike most annual flowers that bloom all season but then die at season’s end, perennials often only bloom for three or four weeks out of the year in exchange for their longevity.
That’s been changing. Breeders and growers have been developing perennial varieties with ever-longer bloom times – including some that bloom and/or rebloom for two months or more.
If you’re interested in these over-achievers, here are eight long-bloomers to consider:
‘Azure Rush’ geranium can bloom for most of the summer. George Weigel
These are different from the common, bushy red annual geraniums (actually Pelargoniums) in that they’re low-growing, arching in habit, and blue, lavender, or pink in bloom.
Sometimes called “cranesbill,” this type of geranium is one of the longest bloomers, usually starting in late May and going at least sporadically for most of the season.
‘Azure Rush,’ Rozanne®, and ‘Johnson’s Blue’ are three heavy-blooming and popular varieties, while the pale-pink ‘Biokovo’ makes a dense, durable groundcover with three to four weeks of late-spring flowers.
Hardy geraniums grow well in full sun to part shade.
'Cat's Pajamas' Catmint. Photo courtesy Proven Winners
This sun-lover would be used much more if it didn’t have “mint” in the name. Catmint isn’t an invasive runner but spreads in a gradually widening clump like most other perennials.
The bluish-green mounded plants produce blue flowers for nearly two months in May and June, then flower again until frost after a cutback to a few inches.
Catmint is a great choice for your hottest, driest, sunniest spots, and although not native, attracts bees and other pollinators.
Cat’s Meow®, Cat’s Pajamas®, ‘Kit Cat,’ ‘Blue Ice,’ and Junior Walker™ are good 15- to 18-inch-tall compact varieties.
Salvia 'May Night'. Photo courtesy Walters Gardens
This heat- and drought-tough, winter-hardy type of salvia blooms with purple flower spikes in May and June, then usually blooms again in late summer if the spent blooms are snipped off and the plants are cut back to about six inches.
‘May Night’ and ‘Caradonna’ are two popular varieties (18 to 24 inches tall), while ‘Marcus’ and Sallyrosa April Night® are more compact at 12 to 15 inches tall.
Salvias do best in full sun and are one of the least favorite deer plants.
Betony ‘Hummelo’ is a summer-blooming perennial that produces flower spikes for months. George Weigel
This underrated cousin of the better known lamb’s ear – that perennial with the fuzzy gray leaves – has waffled green leaves but is a way better bloomer, producing pink-lavender flower spikes for months from June into October.
‘Hummelo,’ the main variety available in commerce, grows 18 inches tall and does well in full sun to part shade. ‘Summer Crush’ is a pink-blooming variety.
Tickseed (Coreopsis verticillata). Gubernat / iStock / Getty Images Plus
Short mounds of lacy leaves produce little buttony blooms of golden yellow starting in June on this native species.
Some of the best ones, such as ‘Zagreb’ and ‘Golden Gain,’ can bloom for nearly four months.
Tickseed grows 15 to 20 inches tall (including the flowers) and does best in full sun.
Anise hyssop (Agastache foeniculum) 'Pink Pearl'. Image courtesy Terra Nova Nurseries
Pollinators love this southwestern-U.S. native with the licorice-scented flower spikes of blue, lavender, and pastel blends that start in June and last until September.
Plants grow two to three feet tall and flower best in full sun.
Good varieties are ‘Blue Fortune,’ ‘Black Adder,’ the apricot-blooming ‘Peachie Keen,’ and the pink-blooming ‘Tutti Fruitti.’ ‘Pink Pearl’ is a new pink-blooming variety.
Allium ‘Millenium’ produces round purple flowers for about eight weeks in summer. George Weigel
Some onion-family plants bloom surprisingly long and well, especially the varieties you’ll find selling in the garden-center perennials section under such names as ‘Millenium,’ ‘Windy City,’ ‘Summer Beauty,’ and ‘Serendipity.’
Plants have strappy, upright leaves and long-lasting, walnut-sized round flowers of pinkish-purple that bloom from late June through August – and sometimes beyond.
Deer, rodents, and most bugs don’t like anything onion-related.
Ornamental onions grow 15 to 18 inches tall and do best in full sun and well drained soil.
Purple coneflowers (Echinacea purpurea). Carmen Agullo Molla / iStock / Getty Images Plus
An old-favorite native perennial, coneflowers now come in all sorts of vivid colors besides the original pale lavender-pink, including red, gold, orange, white, and bright shades of rosy-pink.
Coneflowers have drooping petals around a central brown cone and bloom for weeks from July into September.
They grow 18 to 36 inches tall (depending on variety) and do best in full sun, although they’ll also tolerate a touch of shade.
