singly along a stem but not opposite each other, and about 4-7 inches (5-10 cm) wide. They are roundish and slightly heart shaped with small, fine-toothed edges. Their color is a dull, dark green color above and lighter green underneath. The tops of the leaves are hairless but have tufts of white hairs at the junction of the veins underneath. The leaves often have small blisters caused by aphids and other sap-sucking insects.