Black Leaf Tips on Phalaenopsis: Mineral Buildup and Repotting

Sharon's 5-year-old Phalaenopsis developed black spots on two leaf tips; another plant yellowed leaves. Never repotted. The expert identified mineral buildup in old mix as the cause—symptoms appear first at root tips. Repot annually after flowering in fresh orchid mix. Flush with pure water every two weeks if recently repotted. Reduce fertilizer concentration and frequency. Yellow leaves may indicate root rot from degraded mix.

Follow-up: Sharon confirmed never repotted. Expert approved hydrogen peroxide on cut spots + cinnamon dusting (early day so leaves dry by night). Wait to repot until flowers finish; grow drier meantime. Old mix breaks down, restricts air, stays too wet.