Light: As with most variegated plants, Calathea need plenty of diffused light however direct sunlight will cause the leaves to fade and lose their markings. They can tolerate some degree of shade, but the better the light conditions, the more you will be rewarded by fine foliage. Experiment in your home to find the perfect spot for your plant.
Water: Calathea must be kept in damp soil at all times, but definitely do not allow the plant to sit in water or in very wet soil. Think little and often as a watering policy.
Temperature: Prefers warm to high temperatures, ideally between 18-23°C but can cope with as low as 15°C. Avoid draughts and ensure the plant has reasonable ventilation.
Humidity: High humidity levels are a must. Stand on a wet pebble tray to improve humidity and mist frequently. Pop it in the shower room or kitchen from time to time to give an extra boost.
Feed: Apply a weak dose of a nitrogen rich foliage fertiliser once or twice a month during the growing season.