These popular plants are easily grown from dahlia bulbs or tubers, and generally bloom profusely on four-foot plants. They have a long season, beginning in midsummer and often continuing to produce beautiful flowers until the first frost. Typical of the collarette classification is Double Trouble, a raspberry red dahlia flower with a variegated fuchsia and pink collar. It produces an abundance of blooms, as does La Bomba, a similar collarette that blooms dark red with lighter streaks in its collar florets.
The collarette dahlia type was developed by hybridizers in France and Germany in the early 1900s. The first such flowers were introduced in the U.S. in 1912, and the American Dahlia Society listed the collarette as a form in 1915.
Among the major developers of new collarette hybrids is dahlia guru Bill McLaren, whose introductions often incorporate interesting color variations. His Alpen Lois, for instance, has a corona of flat-plane petals blushing yellow to pink, while the inner petaloids are a blend of white and lavender. Not so colorful, but one of the most striking collarettes, is his Alpen Cherub, a pure white dahlia whose collar petaloids are lime-green at the base. It's a stunning landscape dahlia.
At Lynch Creek Farm, another favorite is Caboose, a colorful collarette whose flat-plane petals are bright red, sometimes streaked with a paler hue, while its collar petaloids are streaked shades of red and yellow. Another prolific bloomer, it provides stunning late-season color bursts in the garden. Like other collarettes, it has nice stem length for flower arranging or bouquets, and it boasts healthy compact foliage. Collarette dahlias are a great choice for the mixed flower bed or border, and they're great show-offs if you grow for exhibition as well.