Florist: Some people like to have green carnations on St. Patrick' s Day. But flowers that are naturally green are extremely rare. Thus, it is very difficult for plant breeders to produce green carnations. Before St. Patrick' s Day, then, it is wise for florists to stock up on white carnations, which are fairly inexpensive and quite easy to dye green.
It is a good idea for florists to stock up on white carnations before St. Patrick's Day most accurately expresses the overall conclusion of the florist's argument.