Peace Lily Care Calendar: What to Do Season by Season

The year at a glance

A peace lily has no true dormancy, but it does slow almost to a stop in the cold, short days. Everything that stresses the plant, repotting, dividing and hard tidying, belongs in the warm half of the year when it can rebuild roots quickly.

These intervals are for an eight inch (21 cm) pot in an ordinary living room. Treat them as a starting point and adjust from what the compost is actually doing.

Spring is when the work happens

As light strengthens and the room warms past about 65F (18C), the plant starts moving and can recover from disturbance. This is the window for repotting, dividing and any serious tidying, and doing it now rather than later gives the plant the whole growing season to re-establish.

Move the plant closer to the window as the low winter sun gives way to a higher, brighter one, but do it in stages. Start feeding again only once you can see new growth, not on a date: fertilizer given before the plant has started moving just loads salts into the compost.

1. Assess the pot Check whether it droops within days of watering, or whether roots are out of the drainage holes. If so, repot now. If not, leave it, because it flowers better snug.
2. Flush the compost Run water through the pot for a couple of minutes to wash out the salts that accumulated over winter. This is the single best thing you can do for brown tips.
3. Clean the leaves Wipe the winter dust off both leaf surfaces. It measurably increases the light reaching the plant just as the growing season starts.
4. Take out the dead Cut yellow and browned outer leaves at the base, along with any spent flower stalks left from last year.

Summer: water and shade

This is the season of fastest growth, heaviest water use and the highest risk of scorch. A position that was ideal in spring can burn the leaves in midsummer, so move the plant back from the glass or add a second layer of curtain before the damage happens rather than after.

Water use can double in real heat, and a pot that lasted a week in spring may need water every third day. Check by weight rather than by calendar. Keep misting the leaf undersides, which suppresses the spider mites that thrive in hot dry indoor air.

Ease off the feeding in genuinely hot weather. When the roots are already struggling above 85F (29C), fertilizer does damage rather than good, and dropped leaves are the usual result.

Autumn: make the switch in good time

As light weakens, a position that was correct all summer becomes too dark, so move the plant back towards the window. Do this while the change in light is still gradual; a plant left in the summer position until midwinter will drop leaves and produce nothing.

At the same time start stretching the watering interval, because the plant is using measurably less. Stop feeding before the temperature falls, since anything left in the compost when growth stops sits there through winter and damages roots.

1. Bring outdoor plants in early Before nights fall below 60F (16C), not after. A single cold night blackens leaves, and a peace lily left out into frost does not come back.
2. Wash before it comes indoors Rinse the leaf undersides and the outside of the pot so you do not carry slugs, mites or gnats into the house with it.
3. Check the heating positions Work out where the plant will stand once the heating is on, before it goes on. The commonest winter damage is a plant left in what turns out to be a hot dry draft.

Winter: hold it, do not grow it

The winter job is to keep the plant alive and undamaged rather than to make it grow. Water rarely, feed not at all, do not repot, do not divide and do not cut anything except genuinely dead material.

The two things that actually kill peace lilies in winter are watering on a summer schedule and cold. Cut the frequency to a third of what it was and keep the volume the same. Keep the plant a foot back from cold glass overnight, and two or three feet clear of any heater.

One or two old outer leaves yellowing over winter is normal turnover. A succession of leaves going is root rot, and the cause is nearly always watering as if it were summer.

Adjusting the calendar to your conditions

The seasons matter far less than the room. A heated flat and an unheated one behave completely differently in the same climate, and a peace lily in a warm bright room may barely slow down at all.

Four things are worth recording through the year, and together they explain almost everything a peace lily does: the date of each watering, the date and size of each repot, the date the first flower bud appears, and the date of any move. Compare one year against the next and the patterns become obvious, from a watering interval that has quietly halved because the pot is full of roots, to a run of yellow leaves that always follows the heating going on.

It is worth noting the position of each plant as well as its care. If you keep more than one peace lily, the difference between the one that flowers and the one that does not is almost always where it stands.