How often should I water a peace lily?

Light

Spathiphyllum tolerates low light better than most flowering houseplants, but it flowers far more freely in bright, indirect light. Direct sun scorches the dark leaves into pale, papery patches. In bright light in summer the calculator suggests every 4–6 days; a plant in a dim room will keep going on much less water, and flower less.

Pot and soil

Peace lilies like their roots fairly snug and soil that stays lightly moist. Use a standard houseplant compost with a little perlite, and water when the top 2–3 cm is dry. They react to the chlorine and salts in tap water with brown leaf tips, so rainwater or filtered water helps. The plant is toxic to cats and dogs if chewed.

Through the year

In medium light the calculator starts at every 5–7 days in spring and summer, 7–9 in autumn, 8–11 in winter, and 10–15 days in low light in winter. Flowering usually comes in spring and early summer, and a plant in flower uses a little more water. Repot every couple of years, as a pot packed with roots dries out faster.

Too much or too little

The droop is the famous one: leaves and flower stems collapse flat over the pot when the soil dries out. A good soak brings it back, but letting it happen every week weakens the plant and leaves yellow, crisp lower leaves behind. Overwatering is quieter and more dangerous: yellowing leaves on damp soil, soft brown roots, and a plant that droops even though the pot is wet.