How to Care for Calathea in Winter
The cold winter months are crucial for the care of calathea, an elegant bulbous flower that is highly sensitive to environmental factors such as temperature and light. Mastering scientific winter management methods can not only help the plant survive the winter safely but also accumulate sufficient energy for blooming in spring. This article systematically analyzes the key points of overwintering care for calathea from four core dimensions.
1. Light Management Strategies
1.1 Full Sunlight Requirement
Ensure at least 6 hours of direct sunlight every day during winter, with a south-facing balcony or window sill being the best choice. It is recommended to use a light meter to monitor, and supplement light promptly when the reading is below 3000 lux.
1.2 Supplemental Lighting Techniques
For consecutive cloudy and rainy days, LED grow lights can be used for supplemental lighting, placed 30-50 cm away from the plant, supplementing 2-3 hours per day. Avoid using incandescent bulbs, as their spectrum is not suitable for plant growth.
2. Environmental Control Points
2.1 Ventilation System
Keep the windows open for ventilation from 10 am to 2 pm every day, for 30 minutes each time. When using an air circulation fan, set it to low speed and maintain a distance of more than 2 meters.
2.2 Temperature Control
Maintain a temperature difference of 15°C at night and 20°C during the day. Users with underfloor heating need to use insulating trays to prevent root burn. Before a cold wave arrives, a temporary insulation shed can be set up.
3. Special Protective Measures
3.1 Coal Smoke Protection
Keep a safe distance of more than 3 meters from heating equipment, and regularly wipe the leaf surface with a damp cloth. It is recommended to use an air purifier to keep the PM2.5 concentration below 35μg/m³.
3.2 Disease Prevention
Apply biological control agents (such as Bacillus subtilis) monthly, and immediately treat scale insects with 75% alcohol locally. Maintain an environmental humidity of 40-60% to prevent sooty mold.
Through the above systematic care, combined with monitoring the substrate moisture (keeping 40% moisture content) and regular pot rotation (rotating 90° weekly), calathea can maintain a healthy state during winter. It is recommended to keep a growth log every month, observing the growth rate of new leaves and the differentiation of flower buds to accumulate data support for spring care.