Do you remember the price you paid for Dahlias? With a little effort you can dig and store them to enjoy again another year. Even if the tops have darkened and shriveled, they are not dead yet because the ground has not frozen and the tubers are intact. That's what counts with bulbs and plants with bulb-like corms or tubers (where the nutrients are stored). However, if you leave them in the ground they'll die.
Dahlias are tropical plants -- native to Mexico and known to have been grown by the Aztecs in the 14th century. Today the American Dahlia Society classifies the wide variety of shapes and sizes into 14 flower types, with colors from white through the color spectrum. Yes, growing Dahlias involves a bit more effort compared with sweet simple daffodils, but the late summer impact and cut-flower value in the vase is hard to beat.
Lift and save
This advice applies to Dahlias, Cannas and any tender bulbs. That includes Gladiolus bulbs -- valuable in the case of some glorious cultivars -- which are not dependably hardy here. Use a digging fork to lift the bulbs or tubers carefully from the ground, and brush off the soil. Avoid shaking them which may break the "neck" that attaches the tuber to the crown. While older textbooks advise us not to wash them off, current instructions encourage washing all the soil off, cutting the stems back to 3 or 4 inches and then air-drying them thoroughly before storage. Some experts recommend division at this point -- cutting the large clumps into individual tubers, each containing some buds or eyes. Others recommend doing so in spring before planting, when the buds (eyes) are most apparent.
Storage recommendations range from spreading them on flats or boxes, in peat moss, sawdust, or sand, to bagging them in paper bags or plastic bags with some ventilation holes. The main thing is the temperature: Dahlias should be kept at 45 to 55 degrees, although a swing from 35 to 50 degrees is tolerable. Unfortunately, modern homes often lack cool basements. In those cases you may have better luck with Cannas, which do best at temperatures around 50 degrees. Check your tubers monthly, and sprinkle with moisture if you see drying and shriveling, and discard anything that is rotting. By March we'll prepare you to pot them up again, to prepare to move outdoors once the soil is warm.
Keep some geraniums, too
The annual geraniums (really Pelargonium) are also worth saving. Either grow them as houseplants in bright light or send them to a 45- to 50-degree basement. The alternative is to cut them back by half and hang them by the roots upside down. (For details, ask a Master Gardener for fact sheets, 652-5400 ext. 137, or visit www.hort.cornell.edu/gardening).
And if all this sounds like too much effort, local growers will prepare new ones for your gardening pleasure when spring warms us once again.
Sally Cunningham is an educator in Consumer/Community Horticulture with Cornell Cooperative Extension of Erie County, and gardening book author.