The U.S. Postal Service celebrates the blooming of summer flowers with a bounty of picturesque Dahlias Forever stamps. Dahlias belong to the prodigious Asteraceae family, which also includes sunflowers, zinnias, asters, rudbeckias, and daisies. Their exuberant blooms have long delighted gardeners and ornamental plant lovers for their remarkable diversity and rich displays of color.
These colorful, floral stamps feature close-up images of dahlias and their pistils. The pink, white, yellow, magenta, and red blossoms were photographed in private gardens by photographer Denise Ippolito using natural light.
Dahlias are native to Mexico and Central America, where they grow as wildflowers and were cultivated in Aztec gardens. Around 1789, the director of the Botanical Garden of Mexico City sent dahlia seeds to the Royal Botanical Garden in Madrid. From there they spread to other European cities where they became popular due to the ease of hybridization and cultivation. Many new types emerged during this time. These gorgeous new varieties prompted a dizzying frenzy of dahlia growing, which reached its apex during the Victorian period.
By the mid-19th century, dahlias had arrived in the United States where they also flourished. Over the years, as backyard gardeners looked to less flamboyant plants that were easier to maintain, dahlias lost favor. Today, they have experienced a resurgence in popularity in the U.S. and worldwide.
The impressive variety in dahlia style and color stems from their octoploid cells, which have eight sets of chromosomes rather than the usual two. Crossbreeding and mutations are common and prolific, resulting in an abundance of new dahlia cultivars each year. Dahlias come in almost every shade except blue and black. So-called "black dahlias" are actually a dark burgundy color.
Shapes range from delicate star-shaped blooms to dense, intricate balls of petals atop sturdy, hollow stems. Their long growing season adds to their demand; dahlias bloom continuously well up to the first frost, delighting admirers the world over.