Leaf drop
A houseplant or shrub dropping many leaves at once, usually in reaction to a sudden change in light, temperature, watering or position.
Also known as: Leaf fall, Defoliation
Symptoms and identification
Healthy-looking or yellowing leaves drop in large numbers, often within days of a change. The plant may be left with bare stems, and new growth can be slow. Leaves fall from the whole plant, or from the older part nearest the base.
Causes
Common triggers are moving the plant, cold draughts, heaters and air conditioners, a big change in light, overwatering or underwatering, root rot, pests such as spider mites and scale, and low humidity. Some plants shed leaves naturally in winter.
Organic treatment
Do not move or repot the plant in response. Check the roots and soil moisture, look for pests, then correct the cause and keep conditions steady. Most plants regrow leaves in a few weeks to months.
Prevention
Keep plants in a steady spot, away from draughts and heaters, and make light or watering changes gradually. Water by checking the soil, not the calendar.
Chemical treatment (use with care)
No chemical treatment is needed for leaf drop caused by conditions. Treat pests if you find them, following the label.