Growing Dahlia Flowers
As your plants grow they will produce many buds, typically with a large central bud and smaller side buds (lateral buds)
To encourage extra large blooms, you can remove lateral (side of the stem) buds, leaving the central bud, and allowing the plant to focus its energy on that one large flower.
Lots of flowers are fun, so no pinching is a fine way to go too. Fertilize monthly up until mid-August with a low-or-no-nitrogen fertilizer.
When the blooms are spent, deadhead the plant to keep flowers coming.
Great as cut flowers, cut the stems long (12-18 inches) to stimulate new growth and of course, new flowers