The ginkgo tree, Ginkgo biloba, a “living fossil” with a lineage over 270 million years, is known for its unique fan-shaped foliage. While traditionally an outdoor tree, its ancient beauty makes it a captivating indoor plant. This article guides you through cultivating this remarkable tree indoors.
Selecting the Right Indoor Ginkgo
Growing a ginkgo indoors requires selecting an appropriate specimen, as full-sized trees quickly outgrow interior spaces. Dwarf cultivars or young trees are preferred for indoor environments. Varieties like ‘Mariken’, known for its compact, rounded growth, or ‘Jade Butterfly’, recognized for its uniquely folded leaves, are popular choices.
When sourcing a ginkgo, inspect the plant for signs of health. Look for vibrant green foliage without discoloration or spots, a sturdy trunk, and a healthy, pest-free root system. Purchase from reputable nurseries or garden centers to ensure a robust specimen.
Essential Care for Indoor Ginkgo
Light Requirements
Indoor ginkgo trees thrive with abundant light. Position your ginkgo in a location receiving bright, direct sunlight for at least six to eight hours daily; a south-facing window is often ideal. If natural light is insufficient, supplemental full-spectrum grow lights can compensate. Maintain grow lights approximately 12 to 18 inches above the canopy to deliver adequate intensity without causing leaf burn.
Watering Practices
Proper watering balances consistent moisture with adequate drainage. Water thoroughly when the top inch or two of soil feels dry. Allow excess water to drain freely from the pot bottom to prevent root rot. Reduce watering frequency during cooler, dormant winter months.
Soil and Drainage
An appropriate potting mix provides structural support, aeration, and drainage for ginkgo roots. A well-draining soil blend is essential to prevent waterlogging. Use a mix formulated for bonsai or succulents, containing components like akadama, pumice, lava rock, or perlite. These materials improve drainage and airflow. Ensure the container has ample drainage holes.
Temperature and Humidity
Indoor ginkgos prefer moderate temperatures during their active growing season, ideally 60-75°F (15-24°C). As deciduous trees, they require a winter dormancy period with cooler temperatures, typically 35-50°F (2-10°C). Moving the plant to an unheated garage or cool basement facilitates this chilling. While humidity is not a primary concern, moderate humidity can be beneficial in dry indoor environments. A pebble tray or room humidifier can help.
Fertilizing
Regular fertilization during the growing season supports the ginkgo’s development and foliage. Begin fertilizing in early spring as new growth emerges and continue through late summer. Apply a balanced liquid fertilizer (e.g., 5-5-5 or 10-10-10) at half the recommended strength every two to four weeks. Cease fertilization in fall and winter for dormancy.
Pruning and Shaping Indoor Ginkgo
Pruning manages the size and aesthetic form of an indoor ginkgo. Its goals include controlling height, encouraging denser branching, and removing dead or crossing branches. Major structural pruning is best performed during the dormant season, typically late winter or early spring before new growth. This timing minimizes stress and allows efficient recovery.
During the active growing season, lighter pruning, like pinching back new shoots, encourages denser growth and maintains the desired shape, creating a fuller canopy. For specific shaping, wiring can guide branch direction. Always use clean, sharp pruning shears for precise cuts, promoting quick healing and reducing disease risk.
Troubleshooting Common Indoor Ginkgo Issues
Indoor ginkgo trees are generally resilient but can show signs of stress or pests. Yellowing leaves, particularly on older foliage, may indicate overwatering or insufficient drainage. Uniformly yellowing leaves across the plant might suggest a nutrient deficiency, correctable with fertilizer. Adjusting watering and ensuring proper soil drainage are often the first steps in addressing leaf discoloration.
Sudden leaf drop outside of dormancy often points to environmental stress, triggered by abrupt temperature changes, insufficient light, or inconsistent watering. Moving the plant to a stable location with consistent light and temperature can mitigate this. Pest infestations are less common but can occur; watch for spider mites (fine webbing, yellow speckles) or aphids (small green/black insects on new growth). Horticultural oils or insecticidal soaps can manage these pests.