Why Are My Plant's Leaves Turning Yellow?

Most yellow leaves come down to water, and far more often it is too much than too little. When soil stays wet, roots cannot breathe, and the plant drops leaves — usually starting low and turning soft and yellow. Lift the pot: if it feels heavy and the soil is wet days after watering, that is your answer.

Underwatering yellows leaves too, but they tend to feel dry and crisp rather than soft. Either way, the fix is the same routine: water only when the top few centimetres of soil are dry, and make sure the pot drains freely.

A plant getting too little light sheds leaves it can no longer support, often yellowing them first. If a plant has been yellowing in a dim corner, move it somewhere brighter but out of harsh direct sun.

Sudden change matters as much as the level. A plant moved from a bright shop to a darker room, or shifted next to a cold draught or a heat pump, will often yellow a few leaves while it adjusts. Give it a stable spot and a couple of weeks before worrying.

If watering and light are right and new growth still looks pale or yellow, the plant may have outgrown the nutrients in its mix. Potting soil is depleted within a year or so. A balanced liquid feed through the growing season, or a refresh of the soil at repotting, usually restores healthy green growth.

Yellowing that spreads between leaf veins while the veins stay green is a classic nutrient signal rather than a watering one.

Not every yellow leaf is a problem. Plants naturally retire their oldest, lowest leaves as they put energy into new growth. One or two yellow leaves at the base, while the rest of the plant looks healthy, is routine — simply remove them.

It is widespread yellowing, fast yellowing, or yellowing on new growth that is worth acting on. Work through watering, light, then nutrients in that order, and most cases resolve.