Calla Lily / Arum Lily
Zantedeschia aethiopica
description
Calla Lily is a rhizomatous plant with elegant funnel-shaped white spathes and lush foliage.
benefits
- Flowering
- Suitable for containers
warnings
- Toxic to cats
- Toxic to dogs
How to care for Calla Lily
sunlight
Calla lilies grow along sunny, damp streambanks in southern Africa. Indoors, give them plenty of light to support sturdy leaves and flowering, while shielding them from harsh summer glass.
Bright indirect light
Place near an east, west, or bright south-facing window with a sheer curtain. This is the most reliable light for a potted calla lily, especially in warm climates.
Gentle direct sun
A few hours of morning or late-afternoon sun can encourage flowering. Avoid intense midday sun behind glass, which can scorch leaves and fade the white spathes.
watering
Keep the soil evenly moist while your Calla Lily is growing. It comes from wet habitats, but in a pot it still needs drainage and should not sit in stagnant water.
Spring - early autumn
Water thoroughly about every 3-7 days, or when the top 1-2 cm of soil feels just dry. Let excess water drain away. Bright light, warmth, small pots, and a leafy plant can shorten the interval.
Cooler or lower-light months
Growth slows in cooler, dimmer conditions, so water roughly every 7-14 days. Check deeper than the surface and wait until the upper few centimetres have dried slightly. If leaves yellow while the mix stays wet, reduce watering.
humidity
Calla lilies grow around moist streambanks and marshes in southern Africa, so they appreciate air that is not persistently dry.
Preferred humidity
Average household humidity of about 40-60% is usually fine when the soil is kept evenly moist during active growth. Prolonged air below 40%, especially near heating or air-conditioning, can cause brown leaf edges and dry flower tips.
How to increase humidity
- Group it with other plants or run a humidifier nearby in dry winter rooms.
- Set the pot on a pebble tray with water below the base of the pot.
- Provide good airflow and avoid constantly wet leaves, which can encourage fungal problems.
temperature
Preferred temperature
Winter minimum indoors
Native to cool, moist South African wetlands, Calla Lily prefers a cooler room over sustained heat. Growth and flowering can slow in temperatures above 27°C (80°F), especially if the compost dries quickly.
nutrition
March - August
Feed every 2-4 weeks while the plant is making leaves or flowering, using a balanced liquid fertilizer at about half the label strength. Stop feeding when growth slows or the foliage dies back for dormancy.
Phosphorus
Phosphorus supports roots and flowering. A balanced fertilizer provides enough without pushing the plant to make leaves at the expense of blooms.
Potassium
Potassium helps support sturdy growth and flowering. Regular light feeding during active growth is more useful than occasional heavy doses.
soil
Rich, moisture-retentive soil with drainage
Calla lily grows from a rhizome and likes soil that stays evenly moist without becoming airless. Use a fertile potting mix blended with compost or coco coir, plus perlite or fine bark to keep excess water moving through the pot.
pH 5,5 - 6,5
This is slightly acidic soil, which suits nutrient uptake. Most quality all-purpose potting mixes fall close to this range, so no special adjustment is usually needed.