Too much direct sun
A leaf turning pale, washed-out yellow on the side facing the window is sun stress.
Diagnosis
Too much direct sun
What's happening
Phalaenopsis grows under the dappled shade of the canopy and isn't built for harsh, direct sun. Strong rays through a window bleach the chlorophyll out of the leaf facing the glass, leaving it pale yellow, sometimes with red-purple blushing or dry tan patches where the tissue actually scorched.
How to fix it
Move the plant back from the window or to an east-facing spot with bright, indirect light, or filter a bright south or west window with a sheer curtain. A healthy moth orchid leaf should be a medium grassy green, not dark green and not bleached. The bleached areas won't fully re-green, but new leaves will come in the right color once the light is gentler.
What fixes it
- A full-spectrum LED grow light — If a harsh window was your only light, a full-spectrum grow light gives even, gentle light without scorching the leaves.
If that doesn't fix it
This is general guidance based on common symptoms; individual plants vary.
Read the full Moth Orchid care guide →
Reviewed June 2026 · how we check this