The Peace Lily, also known as the White Sail Plant or Spathiphyllum, is one of the most popular plants to grow indoors. If people only knew that it filters out five dangerous toxins from the air, it would be the most popular of all!

The toxins include benzene, formaldehyde, trichloroethylene, xylene, and ammonia.

In this guide, you’ll learn everything you ever wanted to know about caring for these beautiful houseplants.​

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Spathiphyllum Overview

Common Name(s) Peace lily, spath, white flag, white sail plant Scientific Name Spathiphyllum Family Araceae Origin Americas and southeastern asia Height Up to 6 fteet Light Medium-low Water Medium, do not over water Temperature 65-75°F Humidity Medium, mist sometimes Soil Moist Fertilizer Use weak fertilizer every few weeks Propagation When repotting, divide the plant Pests Minimal, possible spider mites

Peace lilies are one of the most beautiful houseplants you can grow, if only for the dark green foliage that gracefully arches over. But I don’t think I’m alone in saying that most of us grow them for the gorgeous white blossoms that develop on top of slender, straight stems. The contrast between these blooms and the dark foliage is what makes peace lilies so beautiful.

The flowers are generally taller than the foliage and resemble a calla lily. Flowers start out a pale green and turn to a creamy white as they mature. They’re long lasting blooms and have a very light fragrance.​

Types of Peace Lilies

There are over 40 varieties of peace lily, which is far too many to cover in this article! However, they can be split into the different sizes that they grow as well as the cultivars that are most often found in garden centers:

Small Peace Lilies

​’Power Petite’ is one of the smallest varieties you can grow as it tops out at around 15″ or so.

​Another great choice for a smaller peace lily, ‘Wallisii’ has longer and more rippled leaves but ends up at about 15″ tall as well.

Medium-Sized Peace Lilies

‘Mauna Loa Supreme’ is one of the more common lilies sold around the country. It gets to 3-4′ tall and leaves that can reach 9″ wide.

​’Clevelandii’ grows much shorter than ‘Mauna Loa Supreme’, coming in at 1-3′ tall. However it has leaves that can reach 1.5′ long, making it a unique choice.

Large Peace Lilies

​The largest peace lily variety out there, ‘Sensation’ will reach up to 6′ tall. The leaves will reach up to 20″ long and are quite broad. There’s also a smaller variety known as ‘Sensation Mini’.

Variegated Peace Lilies​

The only cultivar that is variegated, ‘Domino’ is absolutely striking. It looks like someone splashed white paint all over the leaves.

Peace Lily Care

Depending on the type of peace lily you get, it will grow anywhere from 1-6′. They do not have a dormant season unlike many houseplants, so will grow throughout the year. However, they will stop producing blooms in the winter and require less water during that season.

Light

Unlike many plants, peace lilies will thrive in low-light areas. You can place them 5-8 feet from a window and they’ll do just fine. If you place them in direct sunlight for long periods of time, the leaves will yellow, die, and fall off.

If you have no light whatsoever, many gardeners have successfully grown them under T5 fluorescent grow lights. So even in the dead of winter you can enjoy beautiful lilies!

Temperature

Peace lilies should be grown in temperatures ranging from 68-80°F. Don’t place them in a drafty area as they do not like it.

They don’t tolerate extreme cold well, so if your temperatures drop below 45°F, they will most likely die.​

Water

Try to keep your soil evenly moist but not soggy. Standing water will quickly kill the root system. In fact, the most common reason that people kill their peace lilies is because they over-water them. Watering no more than once a week is plenty for this plant. Water even less during winter as the plant won’t be producing blooms.

​You can tell your spathiphyllum needs water when the leaves slightly droop. Don’t wait too long though — severely drooping leaves means the plant has been dry long enough to damage the root system. The bottom leaves may turn yellow and fall off.

Note: the chlorine in tap water can damage your peace lily. If possible, filtered water or leave your tap water out for 24+ hours so the chlorine breaks down.

Soil

A standard well-draining, nutrient-rich potting soil will work well for peace lilies. If you find it holds too much moisture, add some perlite or coarse sand to the mixture.

If you want to make your own potting mix, add equal parts garden soil, coarse sand, and perlite. The soil should be well-aerated and in a pot with a drainage hole to prevent root rot.​

Fertilizer

You can get away without fertilizing your peace lily. But if you do decide to feed it, don’t go overboard. Use a well-balanced 20-20-20- fertilizer but dilute it to 25% of the recommended dose. If you notice the tips of the leaves and blooms turning brown, you’ve probably over-fertilized.​

Fertilize only in spring and summer — it doesn’t grow enough in fall and winter to justify fertilization.​

Repotting

Peace lilies like to be somewhat root-bound. Re-potting is only needed about every other year. When re-potting, place in a pot that is a couple of inches larger than the original pot so that the roots will still be slightly together.​

Here are some signs your plant is too root-bound and needs re-potting:

Your plant is absorbing all of the water you pour on it within only a couple of days

There are crowded roots showing through the bottom of the pot

The stalks are crowding the pot

If you want, you can even re-pot these into coconut husks like this person did.

Pruning​

Pruning isn’t necessary, but you may want to prune anyways to keep your lily looking beautiful throughout the year.

Because every ​stem produces only one flower, once that flower dies it may not look amazing. Cut it back at the base of the stem to remove it and spur new growth.

You can also prune off yellowing leaves or leaves that are drooping severely. While it’s better to prevent these problems in the first place, sometimes the leaves are too far gone and must be removed.​

Propagation

The simplest way to propagate new peace lily plants is by dividing them. New crowns will form at the side of the plant that can be cut away and re-potted.

Choose crowns that have at least two leaves present and use a sharp, disinfected knife to separate them from the parent plant.​

When cutting away the crown, try to get as many roots as you can — this will make it easier for them to establish themselves. Pot the crowns in a 3″ pot in the same soil you use for the parent plant and water immediately.

Avoid fertilizing for at least 3 months or you’ll most likely burn the sensitive new peace lilies.​

Peace lilies clean your air of many toxins, making them a fantastic houseplant to propagate! Jam them into every area of your living space and give all of the extras to your friends and family — they’ll thank you!

Problems

Overall, peace lilies are a resilient houseplant that don’t have much trouble with pests and diseases. However, there are a few key ones to watch out for to keep your plants nice and healthy.

Growing Problems

Yellow leaves indicate too much light, but brown spots are burned areas where direct sunlight hit the leaves.

If your blossoms are green, then you have given your Peace lily too much fertilizer. Reduce it so next season the flowers turn out white.

Pests

Keep pests off by cleaning the leaves regularly. The two that you might get are aphids and mealy bugs.

Aphids are identified by the sticky slime they cover the plant with. Spray your plant with water to get them to fall off, followed by insecticidal soap if they’re still a problem.

For mealy bugs, apply isopropyl alcohol with a cotton ball. If this fails, use insecticidal soap as well.

Diseases

While there are a few rare diseases that affect peace lilies, you’ll most likely run into one of two types of root rot. One of them comes from infected soil, and the other comes from standing, infected water.

To treat root rot, you have to figure out which version your lily plant has. Hint: the most likely culprit is waterborne root rot stemming from watering too often.

Giving the roots a rinse and repotting into a pot with fresh soil will solve both problems.​

FAQs​

Q. I heard I can grow peace lilies indoors under artificial lights, is that true?

A. While they prefer natural light, they can be used in rooms that have no windows at all. They thrive well under fluorescent lighting.​

Q. Can I place my peace lily in a windy area?

A. Peace lilies should be kept out of any drafts or cold air to keep from damaging the plant. They can be misted frequently with warm water and to provide extra moisture, place the pot on top of gravels in the watering dish.​

Q. What should I do with flowers that are dying or dead?

A. Remove any dying or dead flowers, they will take energy away from the plant and cause the new leaves to grow smaller. Remove both the flower and the stalk as far down as you can without damaging the plant.​

Q. All of my blooms have died and my spath isn’t growing new flowers. What to do?

A. If after the blooms die your peace lily just doesn’t seem to want to bloom again, place it in a darker area for awhile. The period of darkness will trick the plant into thinking it’s had a dormant stage and the blooms will soon start to sprout again!​

Q. Are peace lilies toxic to humans?

A. The sap of the plant contains oxalate crystals and ingestion can cause swelling of the tongue and throat. And, can cause dermatitis or skin irritations in some people. An upset stomach is generally experienced if parts of the plant are ingested. But, it would take a large amount of plant ingestion to cause severe problems.

If you experience skin irritation from contact with the plant sap, thoroughly wash the affected area with warm water and soap. If serious symptoms occur from contact or ingestion, contact your physician.

Q. Are peace lilies toxic for my pets?

A. Rumor has it that peace lilies are poisonous for cats and dogs. While this rumor contains some truth, the peace lily is not deadly for your pets. In fact, the plant contains oxalates that will upset the animal’s stomach and drive them to quit eating the plant after only one bite.

Peace lilies win my award for one of the easiest houseplants to take care of for three reasons:

​They can tolerate low-light conditions They show clear feedback when they need water They recover well, even from infestations

The Green Thumbs Behind This Article:

Kevin Espiritu

Founder