Yellow Leaves & Cold Nights: Fixing Phalaenopsis Culture Problems

Yellowing leaves and leaf drop on a Phalaenopsis often signal a combination of poor potting conditions and inadequate temperature. This article addresses both.

Root Zone Rescue: Repot Immediately

• Move the plant from the decorative bowl into a plastic pot with abundant drainage holes.
• Use a standard orchid mix (fir bark, perlite, charcoal)—not moss or soil.
• Rinse roots, trim mushy/stringy ones, and never let the pot sit in standing water.
• Repot after every bloom cycle; mix breaks down fast, suffocating roots.

Temperature: The Silent Killer

Phalaenopsis are tropical—minimum 65°F (18°C) at night. A "cool conservatory" that drops lower causes metabolic shutdown, root rot, and leaf loss. Warmth + airy mix + bright light = healthy orchid.

Light Check

Leaves should be yellow-green, not dark green. Dark green = too little light for blooming. An east window with morning sun is ideal.