Dahlias get fussed over a lot, whether they need it or not, because of the way they swan around, their enormous blooms nodding at you from elongated Audrey Hepburn necks. Baby me, they plead:
Above: In mild climates such as the San Francisco Bay Area where I live, dahlia tubers can stay in the ground year round. In colder climates, dig up your dahlia tubers before the first hard freeze.
Above: The first step is to cut down the stalks, to a height of two or three inches. Photograph by Gardeners Supply via Flickr.
Above: Dig up a whole clump of tubers at a time and be gentle; the tubers are fragile and break apart easily. You can store the dirt-covered clump in a bucket in the basement or, if you plan to divide your dahlias, rinse the tubers before working on them.
Above: Look for tubers with "eyes," swollen buds that indicate the plant has plans to bloom next year. When you divide dahlias, make sure each division has an "eye." A healthy division will spawn its own clump of tubers after you plant it next year. Photograph via SC Dahlias.
Above: To cut apart and slice tubers, you can use a knife, scissors, or pruners, depending on the size of the cut. Photograph by F.D. Richards via Flickr.
Above: A pair of Felco No. 8 Pruners, a precision tool good for separating a nest of tubers at the base (the blades will make cuts as big as 1 inch), is $47.99 at The Felco Store.
Above: During the winter, store tubers in a cool dry spot, in a handful of bark or a bucket of peat moss; you can bag them or keep them in a cardboard box. The dahlia variety Chee is $4 from Frey's Dahlias. Photograph by Ciaobirdie via Flickr.
Above: Return bulbs to the garden in late spring, after the last frost date. Hollyhill Chloe, one of 500 different clumps of dahlias at Golden Gate Park's Dahlia Dell, will grow to a height of five feet, with blooms as big as eight inches in diameter. It's $7 from Corralitos Gardens.
Above: Dahlias like heat, dry feet, and lots of sun. A red and white Skipley Spot dahlia is $7 from Clearview Dahlias.
(N.B.: To tour a dahlia garden in full bloom, see "Dahlia Fever in San Francisco.")