The Calla Lily, scientifically known as Zantedeschia, is a popular ornamental plant celebrated for its elegant, chalice-shaped flowers and lush foliage. Native to southern Africa, these striking plants are admired for their diverse color palette, which includes classic white, as well as vibrant shades of yellow, orange, pink, red, purple, and even near-black varieties. Their distinctive appearance makes them a favored choice for garden beds, containers, and floral arrangements, adding a touch of sophistication to various settings.
Calla Lily Care
Calla Lilies thrive in bright, indirect light, ideally receiving at least six hours daily. While full sun promotes blooming in cooler climates, intense midday sun in hotter regions can scorch leaves, making partial shade preferable. Insufficient light leads to leggy growth and reduced flowers, while excessive direct light can burn foliage.
Consistent moisture is important, but avoid waterlogging to prevent root rot. Water thoroughly about once a week, letting the top inch or two of soil dry between waterings. Overwatering signs include yellowing leaves, a mushy stem base, and a foul odor. Underwatering causes wilting and dry foliage. Potted plants dry faster, needing more frequent checks.
Ideal soil is well-draining, rich in organic matter, and slightly acidic to neutral (pH 5.6-7.0). For containers, a good potting mix includes peat moss or coco coir for moisture retention and perlite or coarse sand for drainage. Proper drainage is crucial to prevent fungal infections from excessive moisture.
Calla Lilies prefer a warm environment, with optimal temperatures ranging from 60-80°F (15-27°C) during the day and no lower than 55°F (13°C) at night. They appreciate humid conditions. Maintain humidity by placing the pot on a pebble tray, using a humidifier, or carefully misting the plant to avoid saturating foliage, which can promote fungal issues.
Fertilization supports robust growth and prolific flowering. Apply a balanced liquid fertilizer (e.g., 10-10-10 or 20-20-20) every two to four weeks during the active growing season (spring and summer). Dilute fertilizer to half strength to prevent root burn. Reduce or stop fertilization in fall as blooming concludes and nutritional needs decrease.
Planting and Growing Calla Lilies
Planting Calla Lilies, whether from rhizomes or potted plants, establishes their growth. Plant rhizomes in spring after the last frost, once soil temperature reaches at least 65°F (18°C). Bury them 3-4 inches deep with “eyes” facing up. Space rhizomes 6-12 inches apart in garden beds, or about 4 inches apart in containers.
When transplanting potted Calla Lilies, choose a container with adequate drainage holes and at least a 12-inch diameter for root development. Fill it with a high-quality, well-draining potting mix. After planting, water thoroughly to settle the soil around the root ball.
Managing Dormancy and Reblooming
Calla Lilies naturally undergo a dormancy period, important for their long-term health and reblooming. Signs include foliage yellowing and dying back, typically in late summer or fall as temperatures cool and growth slows. During dormancy, the plant reduces activity and rests.
As the plant enters dormancy, gradually reduce watering, allowing the soil to dry. Once foliage dies back, rhizomes can remain in the ground in warmer climates (USDA Zones 8-10). In cooler regions (Zones 3-7), dig them up before the first frost, clean, and store in a cool (around 50°F or 10°C), dry, dark environment until spring. To encourage reblooming, bring stored rhizomes out or resume regular watering for potted plants after a 2-3 month dormant period, placing them in a bright location to stimulate new growth.
Common Calla Lily Issues
Calla Lilies can encounter common problems like pests, diseases, and general health concerns. Pests such as aphids, spider mites, and mealybugs feed on sap, causing distorted growth or discolored leaves. Their presence is indicated by visible pests or sticky residue, manageable with insecticidal soap or a mild soap solution.
Root rot, often caused by overwatering or poor drainage, leads to fungal infections. Symptoms include yellowing leaves, wilting despite moist soil, and a mushy root system. Bacterial soft rot also causes soft, mushy stems and rhizomes, often with a foul odor. Prevent these by using well-draining soil and avoiding excessive moisture. Leaf spot diseases, characterized by dark, water-soaked spots, thrive in humid conditions; improve air circulation and avoid overhead watering to help.
General health issues, like overall yellowing leaves, may stem from nutrient deficiencies, insufficient light, or cold temperatures, not just watering problems. If yellowing isn’t due to overwatering, check for nutrient deficiencies and ensure adequate light and warmth.
Toxicity and Safety
Calla Lilies contain calcium oxalate crystals, making all parts toxic if ingested. These microscopic, needle-like crystals cause immediate, intense irritation upon contact. Ingestion symptoms in humans and pets include burning pain in the mouth, lips, tongue, and throat, excessive drooling, swelling, and digestive upset like nausea or vomiting.
While severe symptoms are uncommon, significant throat or tongue swelling can occur, potentially affecting breathing. Skin or eye irritation may also result from contact with the plant’s sap. In households with children or pets, keep Calla Lilies out of reach to prevent accidental ingestion. If ingestion is suspected, seek immediate medical or veterinary attention.