Zantedeschia ‘Red Alert’ (Calla Lily)

Zantedeschia ‘Red Alert,’ commonly known as Calla Lily ‘Red Alert,’ is an elegant and striking cultivar renowned for its bold, crimson-red flowers and glossy foliage. This variety features the classic trumpet-shaped flowers (spathes) that are a signature of Calla Lilies, but with an intense red hue that stands out vividly in any garden or indoor setting. The plant’s overall aesthetic is both dramatic and sophisticated, making it a popular choice among gardeners and floral enthusiasts alike.

Native: Zantedeschia species are native to southern Africa. They belong to the Araceae family, commonly known as the Arum family. This diverse family includes well-known plants like caladium (angel wing) and monstera (Swiss cheese plant).

Plant Type and Habit: Calla Lily ‘Red Alert’ is a tuberous perennial plant with a clumping habit. Multiple stems emerge from a single tuber.

Size: Typically grows 16-20 inches (45-50 cm) tall and spreads approximately 12 to 18 inches (30 to 45 cm).

Flowers: The flowers of this Calla Lily are truly striking. They feature trumpet-shaped spathes that display a vibrant orange-red hue. Measuring up to 3-5 inches (7-12 cm), the spathes have a smooth, waxy texture that enhances their visual appeal. The central spadix contrasts beautifully with its rich orange color, adding to the flower’s overall allure. Red Alert Calla Lilies are known for their extended bloom period, typically flowering from mid-summer to early fall.

Foliage: The foliage consists of large, arrow-shaped leaves that are dark green and speckled with white. This adds an additional layer of visual interest to the plant.

Hardiness: Zantedeschia ‘Red Alert’ is hardy in USDA zones 8 to 10. In these zones, it can be grown outdoors year-round. In colder climates, it is typically grown as an indoor plant or its tubers are lifted and stored over the winter.

Uses: This Calla Lily is commonly planted in garden beds, patio containers, or as a houseplant. Its bold color makes it a favorite for floral arrangements and bouquets.

Toxicity: Calla Lilies are toxic to pets and humans if ingested. The plant contains calcium oxalate crystals, which can cause irritation and discomfort. Symptoms of ingestion may include nausea, vomiting, and oral irritation. It is advisable to keep this plant away from pets and young children.

Deer and Rabbits: Calla lilies are not favored by deer and rabbits due to their toxicity.

Growing and Caring for Calla Lilies

Planting: Calla lilies thrive in well-draining soil rich in organic matter. Plant tubers 4 inches (10 cm) deep in spring after the last frost, spacing them about 12 inches apart. Use a pot with good drainage and a high-quality potting mix for indoor growth.

Light: Place Calla lilies in bright, indirect light. Outdoors, choose a location with morning sun and afternoon shade. Indoors, an east or west-facing window provides optimal light. Avoid direct sunlight, which can scorch the leaves.

Watering: Keep the soil consistently moist but not soggy. Water when the top inch of soil feels dry. Ensure regular watering during the growing season (spring and summer).

Fertilizing: Feed Calla lilies with a balanced, diluted liquid fertilizer every 2-4 weeks during the growing season.

Overwintering: Calla lilies are winter hardy in USDA Zones 8-10, meaning their rhizomes can typically remain in the ground in these warmer climates without protection. In colder climates, dig up calla lily rhizomes before frost. Cut back foliage to 1-2 inches (2-5 cm), clean, and dry the rhizomes at 65-75°F (20-25°C) for 2-3 days. Store in a box with barely damp peat moss at 50-60°F (10-15°C). Check periodically to maintain proper moisture levels.

Propagation: Propagate by division in spring.

With proper care, Calla lilies will reward you with their striking blooms year after year.

Calla Lilies Common Problems

Yellowing Leaves

Overwatering is a common cause of yellowing leaves in Calla Lilies. These plants prefer moist but well-drained soil. Soggy conditions can lead to root rot, which manifests as yellowing or wilting leaves.

Lack of Blooming

Insufficient light can hinder blooming. Calla Lilies thrive in full sun to partial shade. If they are too shaded, they may produce lush foliage but few blooms. Excess nitrogen in the soil, insufficient moisture, inadequate dormancy periods (should last at least 2-3 months), foliage removed too early (preventing the plant from storing enough energy), deficient calla lily rhizomes, and incorrect planting methods could also be responsible for the lack of flowers.

Frost Damage

Calla Lilies are tender perennials susceptible to frost damage. In colder climates, lifting and storing the rhizomes over winter is essential to prevent freezing.

Pests

Aphids: These small, sap-sucking insects can attack the leaves, causing them to curl and become distorted. Aphids can be controlled with insecticidal soap or neem oil.

Spider mites: These tiny pests are hard to see but can cause significant damage, leaving small spots or stippling on leaves. Increasing humidity and using miticides can help control them.

Slugs and Snails: These pests are attracted to the lush foliage and can chew large holes in the leaves. Slug and snail baits, as well as natural deterrents like crushed eggshells, can be effective.

Diseases

Bacterial Soft Rot: This is a common issue where the base of the plant or the rhizome becomes mushy and emits a foul odor. Good cultural practices, such as proper watering and avoiding injury to the plant, are key to prevention.

Gray mold or botrytis: This fungal disease causes gray mold on flowers, leaves, and stems. It thrives in cool, wet conditions. Reducing humidity and improving air circulation can help, as can fungicidal sprays in severe cases.

Root rot: Overwatering can lead to fungal infections in the roots, causing them to rot. Ensuring proper drainage and not overwatering are crucial preventative measures.