Cactus dahlias have fully double blooms showing no central disc. The florets are narrow, pointed and fully revolute for more than one half of their length. They may be straight or distinctly incurving so that the tips point towards the front of the bloom.
Semi-cactus dahlias have fully double blooms showing no central disc. The florets are broad at their bases and pointed at their tips. The centre shall be full and the undeveloped florets immediately round the centre may be flat. Fully developed florets should be revolute for more than one quarter of their length, but not more than half their length.