Dahlia flowers feature array of colors, sizes, forms

Dahlias should be at the height of their loveliness now, as the long bloom season of these bulbous flowers stretches from spring through fall.

Their diversity lets you feature dahlias by themselves in a garden and still enjoy various flower forms, colors, heights and size of individual blossoms. The flowers can range from a few inches across to ones with — no kidding — dinner-plate diameters.

They also thrive in a mixed bed, and dwarf varieties do well in large containers, mixed perhaps with ferns and caladiums.

Sanctuary flowers in country or small-town churches once came from members’ gardens, and they seemed to always feature a few dahlias, even the over-sized ones. I don’t see them often now in local gardens. Cut dahlias last quite a while.

Dahlias are excellent bulbs for cutting, whether for a church bouquet or a dinner table vase. They have long, sturdy stems for holding the weight of each blossom. Cut in early morning when stems contain the most water. Cut on a slant and immerse ends immediately in a pail of tepid water.

To make flowers bush and look fuller, pinch out the terminal bud when leaves first appear and again when the first lateral branches emerge.

If you are competing for a blue ribbon at the fair, encourage huge blossoms by pruning every lateral side shoot, and remove all but the center bud when flower buds appear.

As flowers fade, cut away the heads to prevent seed formation. This increases bulb size which next season will produce a larger flower. Such a practice does not apply to any bulb that is naturalizing, such as daffodil, because they multiply and spread by setting seed.

These tender bulbs must be lifted for winter storage. After frost kills foliage, cut stems to about six inches, then lift them with a spade. Dahlias have a good-sized rootball since their tubers send out long fibrous roots that cling firmly to the soil, and fork tines could tear the rootball too much.

Brush away loose soil, spread tubers on a screen or tray in a warm, dry place. After only a day or two (any longer and they get too dry) pack them individually in dry sand or peat moss in a ziplock bag, to keep them minimally hydrated. Store at about 40 degrees in the coolest part of your basement on uncarpeted floor, or in a garage that gets minimal heat.

Next spring, you’ll have dahlia tubers for a head start on planting your new garden.

Sharon Daniels is a Virginia Cooperative Extension Master Gardener volunteer.