The calathea is a beautiful houseplant with large variegated leaves in colours of green, white, yellow and purple (depending on the species), growing on short stems. It's not an easy plant to grow, but if you are up to the challenge and give it good care, you can be successful.
Provide a calathea with moderate light. Direct sunlight will make the leaf colour less attractive and possibly burn the foliage. A window with direct sunlight coming in should be shaded by a transparent curtain. The best place for a calathea is an east or a west window with either a curtain or shade from a tree.
Increase the humidity of your calathea's environment. High humidity is essential to a calathea and unfortunately, most homes have low humidity. Increase the humidity by placing the plant on a tray of pebbles, placing it around other plants and misting it with soft water daily. Running a humidifier near the plant is a drastic but more successful method.
Give a calathea a temperature of 15 to 21 degrees celsius (60 degrees Fahrenheit to 70 degrees Fahrenheit). A somewhat warmer room will be tolerated, however the warmer the room the more humidity the plant needs. Because increasing the humidity sufficiently is challenging, temperatures less than 21 degrees (70 degrees Fahrenheit) are best.
Water your calathea frequently enough to keep most of the potting mix moist. When the top of potting mix is dry but there's moisture 10cm (several inches) into the soil (gauge by sticking your finger down into the potting mix), it is time to water. The water must be room temperature, so let the water sit in your watering can for 15 minutes before watering.
Check the calathea every spring to see if it needs repotting. If roots have wrapped around the bottom of the plant, move the plant into the next size pot.