The peace lily (Spathiphyllum) is a tropical blooming plant grown outdoors where the climate is mild and frost-free. In its native range, the peace lily grows in deep, well-drained soil rich in organic matter. In the UK, the peace lily is grown indoors because of its ability to bloom and thrive in lowlight situations. The white shell-shaped flowers are held aloft by stiff stems over broad leaves. Like many plants, the peace lily is sensitive to changes in day length, and growth will slow in the autumn and winter. Know, however, that you can save a wilted or browning peace lily.
Look at the peace lily plant to find out why it is declining. Brown margins around the leaves mean too much fertiliser. Yellow leaves mean too much water. Wet soil and wilting leaves also mean too much water. Dry soil and wilting leaves indicates not enough water, while little or no growth during the spring and summer suggests not enough fertiliser or moisture. Suddenly collapsed foliage means the room temperature is too warm or too cold.
Prune out all dead bloom stalks and seriously damaged leaves by pruning them at the base of the stalk near the base of the plant.
Transplant the peace lily into a new clean container that is no more than 5 cm (2 inches) in diameter than the previous container. A larger container allows potting soil not used by the plant to collect moisture. The organic matter in the excess potting soil rots, giving off toxic gasses that not only smell bad, but affect the health of the plant. Use new potting soil or potting soil from a sealed container. A sealed container does not allow airborne disease pathogens or insects to enter. When transplanting, check for excess moisture and mould around the roots of the plant. Cut out any dried or dead roots with hand-held shears. If the root ball is covered with mould, gently wash the entire root ball under a stream of warm water to rinse off the old soil and mould before replanting. Do not damage the roots while washing.
Water the newly transplanted peace lily heavily and allow the water to run through the container. This settles the plant and eliminates air pockets around the roots.
Fertilise with a water-soluble fertiliser recommended for houseplants diluted to 1/2 strength. Using full-strength fertiliser causes the margins of the leaves to turn brown. Fertilise with the diluted fertiliser once a month thereafter. Apply the fertiliser after the plant is deeply watered. Adding fertiliser to a dry plant can damage tender new growth on the roots.
Locate the peace lily indoors where it receives bright sunlight, but not direct sun. The ideal temperature range for growing a peace lily is between 20.0 and 29.4 degrees C (68 and 85 degrees F).
Water with room-temperature water as often as needed to keep the soil in the planting container slightly moist, but not wet. Push your finger into the top inch of soil in the planting container to determine when the plant should be watered. If it is dry, water the peace lily until water runs from the bottom of the container. This flushing action removes accumulated fertiliser salts that cause brown leaf margins. Never allow a peace lily to wilt from not having enough water because of the long recovery period.
If the peace lily collapsed from excess cold or heat, immediately remove it from the area. If the leaves are damaged from the cold, cut off the damaged leaves at the base of the plant after the plant warms and the damaged leaves are clearly evident. If there was too much heat, mist the leaves and water deeply before placing in a favourable environment with the right light and temperature levels.