Quite naturally persons have an idea that the best results will be secured by planting out the whole bunch of tubers, in spring. This is a mistake. One good tuber, with an "eye," or growing point, will make a much better plant than the whole bunch set out together.
To sum up the treatment I advise in the cultivation of the Dahlia:
Have the ground very rich.
Have it worked deeply.
Plant single tubers about the first of June.
Furnish a good support.
See that the ground is well supplied with moisture.
There has been a great change of opinion with regard to the Dahlia. We no longer confine ourselves to one type of it. The single varieties, which were despised of old, are now prime favorites—preferred by many to any other kind. The old very double "show" and "fancy" varieties are largely grown, but they share public favor with the "decoratives," the pompones, and the cactus, and, as I have said, the single forms. Which of these forms is most popular it would be hard to say. All of them have enthusiastic champions, and the best thing to do is to try them all.
"Show" Dahlias are those with large and very double flowers of a single color, and those in which the ground color is of a lighter shade than the edges or tips of the petals. The outer petals recurve, as the flower develops, until they meet at the stem, thus giving us a ball-like blossom.
"Fancy" Dahlias are those having striped petals, and those in which the ground color is darker than the edges or tips of the petals. This class, as a rule, is very variable, and a plant will often have flowers showing but one color. Sometimes half the flower will be one color, half another.