Overwatering & Root Rot
Overwatering is the leading cause of houseplant death. Left unchecked it leads to root rot, which is harder to reverse.
Common causes
Soil stays wet too long
Water only when the top of the soil has dried. Always empty saucers so the pot never sits in water.
Pot without drainage
A pot with no drainage hole traps water at the roots. Repot into one that drains, or use it only as a cachepot.
Established root rot
Mushy black roots and a sour smell mean rot. Unpot, trim away affected roots with clean scissors, and repot in fresh, well-draining mix.