Ubiquitous garden plants, their tall spires of typically blue to purple flowers, during late spring and summer. The individual flowers often have a long spur, reminiscent of Aquilegia and with their colour range and petal arrangement, they look rather like Aconitum. All of these genera are Ranunculaceae. As with Dahlia, many cultivated forms are available, some extremely showy, but we will focus on those closer to the species. D. requienii is a good, easy species to get started with.