Geraniums traveled from South Africa and were cultivated and marveled over in early glasshouses of the 1600s, and we love them still for their varied beautiful leaves and flower colors. Provide well-drained soils and allow the soil to dry before watering thoroughly. Deadhead spent flowers regularly and provide some afternoon shade in hot summer areas, for they do best in low humidity, cool to moderate summer areas. 'Old Scarlet Unique' blooms better than regal types in the often hot and dry weather of summer. Trim to shape right after bloom ends in summer and leave potted plants outdoors until temperatures drop into the 40-45F range, hopefully exposing them to six weeks of cool night temperatures. Bring them into a cool room, around 60F, to overwinter, and their gorgeous blooms will start to unfold in late winter.