For the last few weeks I have been using lots of local dahlias. The colors and varieties are vast and make each flower arrangement unique and exciting. The most beautiful dahlias are delicate and do not travel well...luckily Bob Wollam grows a huge variety of dahlias and brings them into DC several times a week. The size of a dahlia flower can range from 2 inches to 1 foot in size. A little research on why there are so many varieties of dahlias revealed that they are octoplodis, meaning that they have eight set of homologous chromosomes instead of the two sets usually found in plants. This gives dahlias 4 times the ability of most other plants to cross breed into different varieties since homologous chromosomes contain hereditary factors such as color, shape, size and petal configuration. New varieties of dahlias are created from both purposeful and accidental (by bees) cross breeding.
Dahlias are available from mid July through the fall. Bob says that he still has lots of flowers blooming, he is able to protect them from light frosts but once a hard frost hits the season will be over.