Watering:
Water the plant whenever the top 1″ (2.5 cm) of the potting mix has dried.
Fertilizer:
Apply any organic fertilizer once or twice during the growing season.
Re-potting:
The best time to re-pot a Calathea is in early spring, although you can re-pot at any time of year.
Temperature:
Calathea Medallion dislikes direct sunlight. The ideal temperature range for Calathea plants is 65°F to 80°F (18 – 27°C).