Dropping Leaves on indoor lemon
What's Happening
Rapid leaf drop in indoor lemon trees is primarily caused by acclimation shock when moving from high-humidity outdoor environments to dry indoor air (RH <40%), combined with winter light deficiency causing a photoassimilate deficit. Low root-zone temperatures (<50°F) or cold irrigation water can also trigger defensive abscission.
How to Fix It
- 1
Increase humidity to 50-60% using a humidifier, pebble trays, or grouping plants; mist foliage twice daily during the first 2 weeks of transition.
- 2
Install supplemental full-spectrum LED grow lights for 12-16 hours daily to maintain energy production.
- 3
Keep root zone warm (>55°F) using seedling heat mats if positioned near cold windows or floors.
- 4
Water with room-temperature water only to avoid root thermal shock.
How to Prevent It
Acclimate gradually over 2 weeks by increasing indoor time daily. Maintain consistent high light and humidity levels year-round. Avoid frequent indoor/outdoor transitions during temperature swings.