Far more houseplants die from love than from neglect. Overwatering suffocates roots: waterlogged soil holds no oxygen, roots start to rot, and a rotting root system cannot move water even though the soil is soaked. That is why overwatering so often looks like drought.
1. Yellowing lower leaves
Old leaves turn evenly yellow and let go at a touch. One yellow leaf now and then is age. Several at once, low on the plant, with damp soil, means the roots are struggling. Fix: let the top few centimetres dry out completely before you water again, and never leave water standing in the saucer.
2. Soil that stays wet for a week or more
Healthy roots in a right-sized pot drink a pot dry in about a week. Soil still damp on day seven means the pot is too big, the mix too dense, or the light too low for the water you are giving. Fix: move the plant somewhere brighter, and at the next repot choose an airier mix and a snugger pot.
3. Drooping that watering does not cure
An underwatered plant droops and revives within hours of a drink. An overwatered plant droops because of the drink, since its rotting roots cannot deliver water however much you add. When watering makes things worse, stop watering and read the rescue plan below.
4. Fungus gnats
Those small black flies breed in the top layer of constantly moist soil. They annoy more than they damage, but they work as a moisture meter: gnats mean the surface never dries. Fix: let the top 2-3 cm dry between waterings and the population collapses on its own.
5. A musty smell or mushy stems
Healthy soil smells earthy. Rot smells sour and swampy. Brown, soft stems at the soil line mean the rot has moved above ground. Fix: act today rather than next weekend.
The rescue plan for a soggy plant
Slide the plant out of its pot and look at the roots. Healthy roots feel firm and pale. Rotten ones are brown, slimy, and pull apart between your fingers. Trim everything rotten with clean scissors, let the root ball air for an hour, then repot into fresh, airy mix in a pot with a drainage hole, the same size or one smaller. Water once, lightly, then wait until the top of the soil dries. Most plants caught at stages 1 to 4 recover within a month.