Calathea plants are popular for their striking, often patterned foliage, adding a vibrant touch to any home. However, they are particular about their watering needs. Proper watering is crucial for maintaining their health and ensuring their leaves remain vibrant and unfurled.
Essential Watering Practices
Calatheas are sensitive to chemicals in tap water, such as chlorine and fluoride, which can lead to brown leaf edges or spots. Distilled, filtered, or rainwater is ideal to avoid mineral buildup. If tap water is the only option, allow it to sit out overnight to dissipate some chlorine.
Water Calatheas by checking soil moisture, not a strict schedule. The top 1-2 inches of soil should feel dry before watering again. While some suggest watering every 5-7 days during active growth, this varies by environment. Keep the soil consistently moist but never soggy.
Water thoroughly until it drains from the pot’s bottom. Promptly remove any excess water from the saucer to prevent the plant from sitting in standing water, which can lead to root rot. Bottom watering is an alternative: place the pot in a water tray, allowing the plant to absorb moisture from the drainage holes upwards. This ensures even saturation and reduces fungal issues by keeping the leaves dry.
Identifying Watering Problems
Calatheas display clear signs when their watering needs are not met, whether from too much or too little water. Recognizing these symptoms early helps in timely intervention.
Overwatering
Overwatering often manifests as yellowing leaves, mushy stems, or wilting, even when the soil is wet. Waterlogged soil deprives roots of oxygen, leading to root rot. A foul smell from the soil or fungus gnats can also indicate persistent overwatering. If suspected, allow the soil to dry out significantly before the next watering; in severe cases, repotting into fresh soil might be necessary after trimming any rotten roots.
Underwatering
Conversely, underwatering causes crispy or browning leaf edges, curled leaves, and drooping or wilting when the soil is dry. Leaves may curl inward to conserve moisture. Stunted growth can also be a sign of chronic underwatering. Increase watering frequency and ensure consistently moist soil for recovery.
Adapting Watering for Success
Several environmental factors influence a Calathea’s water absorption and evaporation rates. Adjusting the watering routine based on these variables is important.
Humidity
Humidity plays a significant role in a Calathea’s moisture needs. Higher ambient humidity reduces water evaporation from leaves and soil, requiring less frequent watering. In low humidity environments, Calatheas may require more frequent watering to prevent crispy leaf edges and maintain turgidity. Aim for humidity levels between 50-80% for these tropical plants.
Seasonality
Seasonality directly impacts a Calathea’s growth cycle and water consumption. During active growing seasons (spring and summer), plants require more frequent watering as they are actively photosynthesizing and transpiring. In contrast, during dormant fall and winter months, the plant’s growth slows, and water needs decrease, so reduce watering frequency.
Potting Mix
The composition of the potting mix affects moisture retention and drainage. A well-draining, moisture-retentive mix is ideal for Calatheas, often containing peat moss, perlite, vermiculite, and bark. Dense or compacted soil can lead to waterlogging, while overly fast-draining mixes may cause the plant to dry out too quickly.
Pot Type and Size
The type and size of the pot also influence watering frequency. Terracotta pots are porous, allowing water to evaporate faster than plastic or glazed ceramic pots. Larger pots retain moisture longer than smaller ones. Plants in brighter light conditions use water more quickly due to increased photosynthesis and evaporation, requiring more frequent watering than those in lower light.