By Leslie Watkins

Dahlias are among the darlings of the specialty cut-flower world. They are big, bold and beautiful in both gardens and arrangements, and if conditioned and cared for properly they will last five days or more in a vase. They are available in every color except blue, and flowers range in size from one-inch dwarfs to 14-inch giants. The best bloom time for dahlias in New England is September when they fill gardens with dazzling color and provide honeybees, migrating butterflies and hummingbirds with food for their long journey south.

Dahlia, by Leslie Watkins © 2018.

Dahlias originated in the highlands of Mexico and Central America. They were introduced to Europe in 1789, when samples were sent from the Botanical Garden at Mexico City to the Royal Gardens of Madrid. There the genus was named after Andreas Dahl, a Swedish botanist. It was awhile before dahlias were successfully cultivated in Europe. After a few false starts, they took off during the 1800s and 1900s when thousands of new forms were developed. Today there are more dahlia hybridizers than ever before, offering more than 50,000 varieties to chose from. Dahlia flower types include waterlily, cactus, peony, pompon, ball, orchid and daisy.

The dahlia is the national flower of Mexico, where the Aztecs grew them as a food crop and used them to treat epilepsy. Before insulin was discovered, dahlia sugar was used to treat diabetics, and researchers are currently studying them for the possible treatment of kidney and liver issues.

The tubers can be prepared like potatoes and are just as versatile and possibly more flavorful. Peel, grate and squeeze them dry, mix with onions, flour and eggs. Season the mixture with salt, pepper, nutmeg, and fry in olive oil for delicious fritters. The original flavor has largely been bred out over the centuries by hybridizers focusing instead on the blooms, but there are a number of people today who are back-breeding heirloom varieties to get closer to those that were once used as food. The cultivar Blackjack is said to taste like asparagus, and Buga München is reminiscent of parsley. The colorful florets are also edible and may be used in salads and desserts, as appetizers and for cake decoration.

Dahlia tubers are planted in the spring when the soil has warmed to 60 degrees in a sunny location. Set them about six inches deep in rich, well drained soil. They will benefit from an addition of bone meal. Apply slug pellets immediately after planting. Watch carefully for signs of slugs, snails and voles, which enjoy eating tender dahlia shoots alfresco. Space them according to type and stake them well. Some can grow as high as seven feet. Do not water until you see new growth, then water regularly. Pinch off the tops when they reach 12 inches to promote bushy plants. Dig the tubers up after first frost and place them in crates, drawers or boxes layered between slightly moist peat moss and newspaper. Store at just above freezing in a cool, dark place and check once a month that they do not dry out.

Collect the flowers often for bouquets—the more you cut, the more they will bloom. Cut blossoms when nearly mature in the early morning. To condition the flowers, place the just-cut stems immediately into two to three inches of very hot water and let stand until cool before arranging.

Dahlia Salad Recipe (adapted from Mother Earth News)

3 large carrots, diced

1 pound dahlia tubers, pared and diced

1/2 pound fresh green string beans, chopped

1/2 cup virgin olive oil

3 tbsp vinegar

Mayonnaise to taste

Salt and pepper to taste

1 hard boiled egg, quartered

Mixed chopped fresh herbs such as dill, parsley or chives

Steam the carrots, dahlia tubers and beans for five minutes or until still slightly al dente. Put the vegetables in a large mixing bowl and add the oil and vinegar while still hot. Let the vegetables cool, and then add enough mayonnaise to coat the vegetables evenly. Garnish with hard-boiled egg and chopped herbs. Serve at room temperature.

10 Best Dahlias for Cut Flowers

• Appleblossom
• Bracken Palomino
• Bridezilla
• Café Au Lait
• Cara Elizabeth
• Cornel Bronze
• Diva
• Hollyhill Black Beauty
• Lavender Perfection
• Sherwood Peach