Calathea plants are popular indoor plants, known for striking foliage and unique patterns. These tropical plants, often mistakenly referred to as “caler” plants, are admired for vibrant colors and the fascinating way their leaves move, folding up at night and unfurling with morning light. They add a captivating touch of the rainforest indoors.
Understanding Calathea Care
Light Needs
Calatheas thrive in bright, indirect light, mimicking their natural rainforest habitat where sunlight is filtered by tree canopies. An ideal spot is near an east, south, or west-facing window with sheer curtains. Direct sunlight can scorch delicate leaves, causing them to fade or develop brown spots.
Watering and Humidity
Calatheas need consistently moist soil, but never soggy. Overwatering leads to root rot, while underwatering causes leaves to wilt or curl. Using distilled, filtered, or rainwater is recommended, as Calatheas are sensitive to chemicals like chlorine and mineral salts that can cause browning leaf edges. High humidity, ideally 50% or higher, is also important. Increase humidity with a pebble tray, by grouping plants, or using a humidifier.
Soil and Nutrients
A well-draining, aerated, and moisture-retentive potting mix is best for Calatheas. A suitable blend often includes potting soil, perlite for drainage, and peat moss or coco coir to retain moisture. During the growing season, from spring through summer, fertilize monthly with a balanced liquid fertilizer at half strength. Reduce or stop fertilization during autumn and winter when growth slows.
Troubleshooting Common Calathea Issues
Addressing Leaf Problems
Crispy or brown leaf edges indicate low humidity or inconsistent watering. Increasing ambient humidity and ensuring regular, even watering helps. Yellowing leaves, especially with a mushy stem, indicate overwatering and root rot, requiring improved drainage and allowing the soil to dry more between waterings. Fading leaf patterns or brown spots result from too much direct sunlight; move the plant to a shadier spot.
Managing Pests
Calatheas are susceptible to common houseplant pests, especially in dry conditions. Spider mites cause stippling, discoloration, and fine webbing, thriving in low humidity. Mealybugs appear as white, cottony masses on leaf undersides and in axils, feeding on plant sap. Aphids are small, soft-bodied insects that congregate on new growth, causing leaf deformation and yellowing.
Gently wiping leaves with a damp cloth removes some pests, while insecticidal soap or neem oil are effective for significant infestations. Maintaining higher humidity also deters spider mites.
Propagation and Repotting
Calathea plants are best propagated by division, typically during spring repotting. Separate the plant’s rhizomes into smaller sections, ensuring each has roots and several leaves. Pot each section in fresh, well-draining soil and provide warm, humid conditions.
Calatheas do not require frequent repotting, usually every one to two years, or when root-bound. Repotting signs include roots emerging from drainage holes, stunted growth, or the plant drying out too quickly. Choose a pot only one or two inches larger in diameter than the current one to prevent excess soil from retaining too much moisture, which can lead to root rot. Repot in early spring, before the active growing season begins.