Can a Peace Lily grow in water alone, with no soil at all? You’ve probably spotted some online photos of plants raised this way, or maybe even seen some in person. Though hanging plants like Pothos or Philodendron are more common choices, a Spathiphyllum can also grow in a hydroponic setup. Here’s our detailed guide to keeping Peace Lilies in water.
Peace Lilies can grow in water as long as you provide some nutrients and replace the liquid regularly. Distilled water and hydroponic fertilizer work best. Change the water out every two weeks, scrubbing any algae out of the container. You should also monitor the pH and keep it between 5.8 and 6.5.
It’s important to keep your expectations realistic. Your aquatic Peace Lily probably won’t grow as fast or as large as it would in potting mix. And unless you’re diligent with your care routine, it may not live as long. However, if you follow our advice below, your Peace Lily will have a good shot at thriving in water.
Should You Grow Your Peace Lily in Water?
If you’ve never tried growing a plant in a liquid-only medium, you might be wondering what’s the point. As it turns out, there are a few advantages to growing a Peace Lily in just water. There are some trade-offs as well – we’ll break down the pros and cons.
Pro: No Watering Worries
Keeping your Peace Lily’s roots underwater pretty much eliminates two of the biggest care challenges: underwatering and overwatering. As long as you don’t let the jar run too low, your plant won’t get dehydrated. And as weird as it sounds, there’s no risk of watering too much when the plant is in water all the time.
That’s because overwatering is a problem of wet soil, not a wet plant. A damp, swampy potting mix cuts the roots off from their air supply. It also lets microbes breed in huge numbers, causing root rot. But those microbes don’t live in pure water. As for airflow, a partly submerged Peace Lily can grow special roots that extract oxygen from water.
This also means you don’t need to keep checking your Peace Lily’s soil to see if it’s dry. You have to refill the jar periodically, but still less often than you’d water a potted plant during the summer.
Con: More Maintenance
On the other hand, when the time comes to refresh the water, there’s a bit more work involved. You’ll have to take your plant out of the jar and clean out any algae before refilling it. You’ll also have to add some fertilizer and make sure the pH is balanced. The upkeep for a water-dwelling Peace Lily is more complicated than it is for a normal potted plant.
Pro: You Can Look at the Roots
Hydroponic Peace Lilies don’t need drainage holes in their pots. That means they can live in mason jars, vases, and other glass or plastic containers. With this arrangement, checking on the root system is as easy as looking through a window.
That’s great for monitoring your Peace Lily’s health. Though root rot isn’t nearly as common in water, some kinds of algae can still attack your plant. With a glass container, you can see this happening and stop it before it spreads too far.
As a bonus, those curling, trailing water roots look pretty cool. You can even jazz them up with some decorative rocks or beads.
Con: Limited Growth
Peace Lilies can adapt remarkably well to living in water, but it’s not what they’re built for. These plants like to grow in the loose carpet of rotting twigs and leaves that covers the rainforest floor. Water roots won’t let them grow as rapidly as soil roots.
And a Peace Lily isn’t a very fast-growing plant even in ideal circumstances. If you grow it hydroponically, you may find it hard to tell if it’s getting bigger at all! It will probably never reach its normal mature size.
Many sources say that Peace Lilies grown in water will only survive for a year or so. We’re not sure where this idea came from. Maybe there are too many people out there who thought they could just stick their plants in a jar and forget about them. Your water-rooted Peace Lily may not get huge, but with proper care, there’s no reason it can’t survive for years.
Pro: Easy Repotting
If your Peace Lily does grow enough that it needs a bigger container, it’s easy to move. Uprooting a soil-grown plant can be kind of a pain, and it tends to make a mess. Transplanting a hydroponic Peace Lily is as simple as sliding it out of the jar and into another.
Growing a Peace Lily in Water: Your Step-by-Step Guide
Let’s get into the nitty-gritty of how to grow a Peace Lily hydroponically. This guide assumes you’re starting with a plant that’s rooted in soil, or one you’re propagating by root division. If you bought a water-rooted Peace Lily and just need care instructions, skip to Step 5.
Step 1: Prepare Your Container
You can place your Peace Lily in just about any watertight container as long as it’s large enough. However, we’d probably go with glass or plastic. Why bother keeping a Peace Lily in water if you’re not going to be able to see the roots?
Be aware that algae grow more easily in a more transparent container. This shouldn’t be an issue as long as you change the water and clean the vessel regularly. Still, it’s worth keeping the tradeoff in mind.
Also, you’ll need to be picking your plant up out of the pot every so often. That will be easier if you choose a container with a wide mouth.
Don’t worry, your Peace Lily will float. However, it’s often helpful to weigh down the roots so that the plant can stand up straight. You can use pretty much any type of decorative rocks for this. Or get colorful with some glass pebbles or marbles. Clean them off first – in fact, it wouldn’t hurt to disinfect them with some rubbing alcohol.
Step 2: Uproot Your Peace Lily
Hold your plant with one hand at the base of its stems. With the other, tilt the pot over and slide your Peace Lily out. If it’s been in the same container for a long time, the roots may be tight. A few sharp smacks on the base of the pot should jog them free. If the pot is made of flexible plastic, you can squeeze the sides to loosen the soil.
Now clean all the soil off your Peace Lily’s roots. We recommend rinsing them in water or even hosing them down a bit to get rid of all the grit. Be gentle, but don’t sweat it if you break a few roots. Your plant can bounce back as long as it still has at least ⅔ of its root system left.
Step 3: Transfer Your Plant
Now it’s time to place your Peace Lily into its new vessel. Tuck it into the container and settle any anchoring rocks around the roots. Then fill your jar or vase with water until the roots are covered. Use distilled water or rainwater if possible. Tap water is okay, but it often has more mineral salts than a Spathiphyllum prefers.
Don’t add any fertilizer just yet. The plant will be stressed for a while after you move it into the water. Fertilizing at this stage could harm it.
Step 4: Get Your Peace Lily in Place
Peace Lilies do best in bright, indirect light. Find a spot where your plant will get a lot of sun reflected off the walls or filtered through curtains – but none shining right on its leaves. Your Peace Lily needs time to adjust to its new environment. During this period, it’s even more vulnerable to sunburn than usual.
Your Peace Lily is likely to slouch dramatically after being so rudely evicted from the soil. This is normal, and not a reason to panic. Your plant should straighten back up after a few days.
The next step is mostly about waiting. It will take your Peace Lily at least a few weeks to grow water roots. They’re thin and wispy compared to the soil roots, though they often grow from thicker greenish rhizomes. Once the roots are at least an inch long, it’s safe to say your plant is settled in.
Step 5: Long-Term Care
Now it’s time to keep your Peace Lily growing for the long haul. For the most part, it needs what every Peace Lily needs:
- Bright, indirect sunlight. At least 6-8 hours per day is ideal, especially if you want it to flower. Once the water roots grow in, it’s even safe to let your Peace Lily get a little direct sunlight. Limit it to about 2 hours per day, though. And if algae start to grow, you might want to move your plant back to the shade.
- Water. Change the water in your plant’s container every 2 weeks. This will help keep it oxygenated and stop scum from forming. Every so often, you may want to scrub the vase and any rocks with soap and water. Rinse them well before putting your Peace Lily back. Again, distilled water is best.
- Fertilizer. Store-bought potting soil often has lots of nutrients to keep your Spathiphyllum healthy. Water doesn’t. You’ll need to add some – we recommend using a hydroponic fertilizer like this one. Be sparing with it, since Peace Lilies don’t require tons of fertilizer. A few drops added every time you change the water should do the trick.
- Warmth. Temperatures between 65 and 85 degrees will keep your Peace Lily comfortable. Avoid letting them dip below 55 or above 90. Extreme temperatures can cause a shock to your plant’s system.
The other thing to remember is that you’ll need to maintain the right pH. For Peace Lilies, this is between 5.8 and 6.5, a mildly acidic range. Soil acts as a natural pH buffer, helping to keep the acidity stable, but water requires some fine-tuning.
We recommend getting a hydroponic pH kit. Whenever you change your Peace Lily’s water and add fertilizer, you can test the pH and adjust it as needed.
Can You Grow Peace Lilies With Betta Fish?
You may have seen people recommending that you keep a Betta Fish in your Peace Lily’s water jar. Often, they’ll claim that this creates a tiny self-sustaining ecosystem. The Betta supposedly feeds itself by nibbling on your Spathiphyllum’s roots, while fertilizing the plant with its waste.
It sounds like a neat idea, but it’s nonsense. Betta Fish are carnivores. They couldn’t survive on Peace Lily roots if they tried. This idea probably originated with an unscrupulous pet store owner who figured out they could charge more for a fish by plunking a pretty houseplant into its jar.
In theory, you could create a workable aquarium that could host a Betta and a Peace Lily together. However, you’d need to make some serious accommodations for the fish:
- Food. Since it can’t chow down on the roots, you’ll need to feed your Betta regularly.
- Heat. These fish like their water to be around 80 degrees Fahrenheit. You’ll have to include a heater to keep yours from getting sluggish and refusing to eat.
- Air. The Betta Fish has an interesting respiratory system. It has to take in some of its air at the surface of the water. That means you’ll need some kind of barrier to keep your Peace Lily from filling the neck of the container.
- Space. Recommendations for Betta tank size can vary wildly, but 2.5 gallons seems to be the bare minimum. It will be cramped, unhappy, and short-lived in a typical houseplant vase.
Even with all of these modifications, it’s hard to guarantee that this pairing will work. It’s an open question whether a Peace Lily can get all the nutrients it needs from fish droppings. Plus, the upper end of a Spathiphyllum’s pH range is the lowest that a Betta fish will tolerate. Don’t try to pair this odd couple unless you have lots of experience caring for both houseplants and Betta Fish.
Will Semi-Hydro Work for Peace Lilies?
There’s a middle path between full hydroponics and traditional potting soil. It’s called semi-hydroponics, or semi-hydro for short. With a bit of know-how, this can be a great option for your Peace Lily.
In semi-hyrdo, you don’t submerge the roots in water. Instead, they grow in an artificial substrate that can pull moisture up from a reservoir of water at the base. A semi-hydro growing medium consists of chunky, porous, inorganic material that creates lots of air pockets in the pot.
This lets your Peace Lily grow soil roots instead of water roots, enabling more robust growth. But it also provides most of the same benefits as growing plants in water. The main drawback is that the initial setup can be expensive and time-consuming.
Good substrates include:
- LECA. These clay spheres are heat-treated to make them porous. They’re the go-to choice for many semi-hydro growers. LECA is expensive, but you can use it over and over if you clean it well. You can find an in-depth look at LECA in this article.
- Pumice. This volcanic rock is even better at moisture wicking than LECA. It’s also cheaper, though it’s heavier, and it’s harder to find locally in certain regions. Pumice also has a natural, rugged appearance that some growers will like. It looks like what it is – chunks of volcanic rock.
- Perlite. Perlite is volcanic glass that’s been heated and puffed up like popcorn. It’s even cheaper than the other two, though often smaller-grained. Make sure that you get a coarse variety.
How to Grow a Semi-Hydro Peace Lily
There are two ways to create a semi-hydro container for your Peace Lily:
- Fill a net pot with substrate and plant your Peace Lily in that. Then slide this inside a larger cachepot that holds your water reservoir. This arrangement makes it easy to move your plant out of the way when changing the water.
- Use a single tall container with your water in the bottom, your Peace Lily at the top, and your growing medium filling in the middle. This looks a bit more elegant and can make it easier to see what’s going on with the roots.
Before transferring your Peace Lily to semi-hydro, rinse any dust off your substrate. You may also want to sift away smaller bits with a sieve. And if you’re using LECA, you need to soak it in water for 24 hours. This will make the clay marbles swell up to five times their starting size.
Fill your container partway full of substrate. Place your Peace Lily inside, and gently cover up its roots. Shake the container a bit to settle everything in place. Now add some distilled water, making sure that it doesn’t reach all the way to the level of the roots. Ideally, the bottom ¼ to ⅓ of the growing medium should be submerged.
From there on out, semi-hydro is much like full hydro. Replace the water and nutrients every 2 weeks or so, making pH adjustments when necessary. If you see any algae or salty mineral crust forming on your substrate, rinse it thoroughly with distilled water. Otherwise, leave your Peace Lily rooted when you’re dumping out and refilling its reservoir.
Read more about semi-hydro and what you need to do to keep your plants healthy in this article: What is LECA and What Do You Need to Get Started Transferring Your Plants.
Peace Lilies can survive perfectly well in water, though their growth will be even slower than in soil. Their care will be different, but not necessarily harder, and you’ll get the hang of it quickly. We hope our advice comes in handy if you decide to try the experiment for yourself!