This overview will help you identify the cause.
Shock
This is the most common cause of leaf drop and often the hardest to correct.
The opposite is also true: an indoor plant taken outdoors for the summer may also experience shock.
The Spruce / Letícia Almeida
Shock is usually a response to dramatic changes in temperature, humidity, light levels, or watering habits.
The same is true fornewly repotted or divided houseplants.
Through photosynthesis, they can absorb toxins and allergens in homes and offices.
The Spruce / Letícia Almeida
Resting the pot on a tray of pebbles kept constantly wet may help with humidity levels.
Mist the leaves regularly to prevent them from drying out.
Physical Damage
Plants that are in high-traffic areas or are frequently brushed will sometimes drop leaves inexplicably.
The Spruce / Anastasia Tretiak
Pets and children bumping into plants may cause leaf drop.
Pests
Certain pests, such asmealybugs,spider mites, andscalepotentially cause leaf drop.
Check fallen leaves carefully for telltale signs of infestation.
The Spruce / Phoebe Cheong
Low Light
If your plant drops leaves in winter, it maynot be getting enough light.
Extreme Temperatures
Manytropical plantswill begin to drop healthy leaves when they are exposed to cold drafts.
Keep your plants away from extremes of heat and cold.
The Spruce / Letícia Almeida
Over- or Under-Watering
Retaining soil moisture levels is tricky with indoor plants.
Leaf drop occurs either because the soil is too wet or too dry.
Try increasing its feeding schedule to see if that helps.
The Spruce / Krystal Slagle
Why Houseplants Drop Leaves.
University of Vermont Extension.
University of Kentucky Extension.
