Many popular indoor plants—pothos, ferns, calatheas—originate from tropical forest floors where sunlight is always filtered. Placing them in direct sun on an Indian balcony can overwhelm them quickly.
What's happening
Strong sunlight heats leaf surfaces rapidly, killing cells and creating scorched brown patches or bleached spots. Damage is worst on top leaves and the sun-facing side. Plants in dark plastic pots suffer more as the pot heats up and cooks roots.
Why this happens
Single-pane glass in Indian apartments magnifies heat while trapping warm air. West-facing windows are worst—peak sun plus accumulated afternoon heat. Even a few hours of unfiltered summer exposure causes permanent damage on sensitive species.
What usually helps
Position plants one to two feet back from glass, or use sheer curtains. On balconies, place plants behind a railing or taller pot. Switch to terracotta or light ceramic pots. Grouping plants creates a humid microclimate reducing heat stress.
What to expect next
Damaged leaves will not heal—trim the worst ones. New growth comes in healthy within two to three weeks once exposure is reduced.