Calla Lily
General Information: This is an elegant plant from the Cape area of South Africa, where it is known as the pig lily. There it grows from its tuber, almost like a clump of weeds, in an area that is marshy through winter and dry in summer. It is a subtropical plant, able to tolerate quite different day and night temperatures. The Calla Lily has broad arrow-shaped leaves up to 20 inches long and 10 – 12 inches wide on stems of up to 3 feet. Its flowers, which bloom in winter or early spring, are spectacular, having a golden spadix circled by a velvety white spathe.
Light and Temperature: In summer, the rhizome should be planted (in pot or garden) outside in the sun until late autumn. In October, bring it inside and keep in bright light at reasonably low temperatures. When growth starts, keep at 50 – 57° F for 3 months, and then increase the temperature to over 61° F.
Water and Feeding: Keep the rhizome dry in the summer dormancy period. In winter, water little at first, increasing as growth begins. During full growth keep the soil moist and place the pot in a bowl of water. Feed with liquid fertilizer every other week before flowering and weekly when in flower; thereafter cease feeding. Humidity is a natural demand of the Calla during the flowering season, so place over a tray of moist pebbles.
Propagation: Divide the rhizomes in autumn, keeping at least 1 shoot on each portion. Offshoots can be removed and potted.
Repotting: Repot each autumn, in humus-rich compost. There are often up to 3 or more rhizomes in each pot for effect.
Possible Problems: Spray scale insects with insecticide, if infested. Aphids and red spider mite will attack if conditions are too hot and dry. Treat and increase humidity.