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Peace lily leaves turning yellow: causes and what to do

17 results in the diagnosis tree begin with yellowing leaves, 7 of them marked likely when the answers fit. They are ordered here for Peace lily (Spathiphyllum wallisii), using what its sources say about soil moisture, light, soil, watering and feeding and one problem recorded for it.

Sources last read 14 September 2026.

Start the diagnosis for this Peace lily

Peace lily (Spathiphyllum wallisii), the whole plant.
Bernard DUPONT from FRANCE, CC BY-SA 2.0 · Wikimedia Commons

Spathiphyllum wallisii, commonly known as peace lily, white sails, or spathe flower, is a very popular indoor house plant of the family Araceae. The genus name means "spathe-leaf", and the specific epithet is named after Gustav Wallis, the German plant collector. Wikipedia, CC BY-SA 4.0

Native range: Colombia to Venezuela (wet tropical). Also sold as Spathe Flower and white sails.

What Peace lily’s sources say that bears on this

Soil moisture
Moist but well-drained
RHS · read 11 September 2026
Light
Medium light
Clemson Extension · read 11 September 2026
Partial shade
RHS · read 11 September 2026
Soil
Chalk, Loam, Sand; pH Acid or Alkaline or Neutral
RHS · read 11 September 2026
Watering
Keep the soil moist without letting it get soggy, and let it dry between waterings. Peace lilies respond well to bottom watering.
NC State Extension · read 13 September 2026
While growing, water and mist generously and keep humidity high.
RHS · read 13 September 2026
Feeding
Feed at a quarter of the label strength, and flush the soil between feeds. Too much fertilizer and a build-up of salts can burn roots and leaf tips.
NC State Extension · read 13 September 2026
Feed monthly with a balanced liquid fertiliser.
RHS · read 13 September 2026

How this shows up on a Peace lily

Soft yellow leaves low on the plant, soil still wet

On a peace lily the yellowing climbs from below. Affected leaves feel limp rather than papery, and water sits in the saucer long after it drains through.

Its source calls for soil that is moist but well-drained. Past that, water in the pot displaces the air the roots need, and damaged roots then fail to supply the leaves above them.

Telling it apart: Whether the compost has dried at all since the last watering. A pot that has not dried in a fortnight is answering the question on its own.

RHS · read 11 September 2026

Possible causes, likeliest first for a Peace lily

  1. Most likely too much water

    Ranked higher because Peace lily's recorded problems point this way.

    • Moist but well-drained RHS · read 11 September 2026
    • Chalk, Loam, Sand; pH Acid or Alkaline or Neutral RHS · read 11 September 2026

    Why: Soil that is wet two inches down, under leaves that are yellowing from the bottom or falling, points at roots that cannot breathe.

    What to try:

    • Hold off watering until the top two inches of soil are dry, and check again with a finger rather than by the calendar.Useful: moisture meter
    • Empty any water standing in the saucer or the outer pot within half an hour of watering.Useful: pot with drainage holes

    What would settle it: Lift the peace lily out of its pot. Healthy roots are firm and pale; roots that have been wet too long are brown, soft and smell sour.

    Check this with the questions

  2. Most likely cold

    Ranked higher for Peace lily because of what its sources say.

    Its RHS hardiness rating puts this plant's cold floor at 10°C or above, so a cold windowsill at night is a strong explanation.

    • H1B — 10–15°C RHS · read 11 September 2026

    Why: Soft, dark patches rather than crisp ones are damaged tissue rather than dried tissue.

    What to try:

    • Move it away from the glass at night, or keep the curtain on the room side of the peace lily.
    • Leave damaged leaves until new growth appears, then remove the worst of them.

    What would settle it: Where the peace lily sits at night, and what the glass feels like at that hour. Damage that appeared after one cold night, on the side facing the window, is the pattern.

    Check this with the questions

  3. Most likely too little water

    • Moist but well-drained RHS · read 11 September 2026

    Why: Soil dry two inches down, under lower leaves that are yellowing or leaves that are falling, is a peace lily shedding what it cannot support.

    What to try:

    • Water until it runs from the drainage hole, then let the pot drain.Useful: pot with drainage holes
    • If the water runs straight through a shrunken rootball, stand the pot in water for twenty minutes so the compost can take it up.

    What would settle it: Water it thoroughly and look again the same evening. A thirsty plant firms up fast. One that does not has a root problem rather than a water problem.

    Check this with the questions

Less likely for a Peace lily, still possible

Questions

What usually causes yellowing leaves on a Peace lily?
For Peace lily: most likely too much water, most likely cold and most likely too little water.
How can I tell which one it is on my Peace lily?
Where is the yellowing? The lowest leaves, working upward; New growth at the top, while older leaves stay green; Between the veins, the veins themselves still green; At the leaf tips and edges, browning as it goes; Patchy, only on the side facing the window.
What do Peace lily's sources say about its soil moisture?
RHS: Moist but well-drained.
What does this look like on a Peace lily?
On a peace lily the yellowing climbs from below. Affected leaves feel limp rather than papery, and water sits in the saucer long after it drains through. Telling it apart: Whether the compost has dried at all since the last watering. A pot that has not dried in a fortnight is answering the question on its own.
Is Peace lily safe to handle while I check it?
Its sources list it as toxic to cats, dogs and people. Wash your hands after handling the roots or sap, and keep trimmings away from pets.

Something else wrong with the Peace lily?

Everything the sources say about Peace lily

What this does not cover

This page orders a decision tree's results using a plant's sourced care. It has not seen your plant, its pot or its window, and two problems at once are common: that is the usual reason a confident answer turns out wrong. The questions in the diagnosis tool narrow it further than a list can.