Can you water plants with distilled water? Yes. Do you need to? For most houseplants, probably not. The real question is what’s in your tap water, and which of your plants care about it.
Here’s what distilled water is, which plants actually do better with it, and what else works if you’d rather not haul jugs home from the store.
What Is Distilled Water?
Distilled water is water that has been boiled and collected again as condensed vapor. Ready.gov, the federal emergency-preparedness site, says distillation removes germs that resist boiling and chlorine, as well as heavy metals, salts and most other chemicals.
That cleanup works both ways. Virginia Cooperative Extension notes that distilled water tastes “flat” because the minerals naturally present in water are removed during the process. Some of those minerals are plant food: the calcium and magnesium in hard water are plant nutrients. Distilled water hydrates a plant, but it doesn’t feed it.
Is Purified Water the Same as Distilled Water?
Not always. Under the FDA’s bottled water rules, “purified water” can be made by distillation, deionization, reverse osmosis or other suitable processes, and it can be called “distilled water” only if it was made by distillation. Spring water is a different product: it is defined as water from an underground formation that flows naturally to the surface. It is not distilled water.
For plants, the label matters less than one question: does the process remove fluoride? Distillation and reverse osmosis do. More on that below.
Do Houseplants Really Need Distilled Water?
Most don’t. University of Missouri Extension says ordinary tap or well water is usually satisfactory for plants, and that “chlorine and fluorine often added to city water do not harm plants.” It also calls rainwater and melted snow excellent water sources.
Other extension sources are more cautious. A University of Illinois Extension horticulture post advises using distilled water rather than tap water, because tap water contains fluoride that causes leaf tip burn on many plants, with peace lily and spider plants among the most vulnerable.
Put those together and you get a practical answer: tap water is fine for many houseplants, but a short list of fluoride-sensitive plants, plus carnivorous plants like the Venus flytrap, do better with distilled water or rainwater.
What’s in Tap Water, and What Gets It Out
City tap water may be disinfected with chlorine or chloramines, and the Pacific Northwest Plant Disease Management Handbook says many municipal water sources add fluoride to prevent tooth decay. Each one behaves differently once it’s in your watering can.
Chlorine: Letting It Stand Works
Chlorine is the easy one. A Penn State horticulture specialist says chlorine can be removed from water by heating, aeration, or filling watering containers and letting them stand overnight before watering.
Chloramine: Standing Won’t Remove It
Some cities disinfect with chloramine (monochloramine) instead. The EPA says allowing water to sit at room temperature does not remove monochloramine, boiling does not remove it, and reverse osmosis filters do not remove it. Activated carbon filtration can be effective at removing chlorine and chloramines. Not sure which one your city uses? Your water utility can tell you.
Fluoride: Standing Won’t Remove It Either
Letting tap water stand removes chlorine, not fluoride. Inorganic fluorides in water usually remain in solution as fluoride ions when the water is relatively low in pH and hardness, and fluoride is an accumulative poison in plant foliage. Typical symptoms on broadleaf plants are dead leaf tips and margins that spread inward.
Many public water sources contain trace amounts of fluorides, and given enough time, sensitive plants can accumulate enough from that water to develop toxicity symptoms. You may see advice that fluoride evaporates if water sits for a day. That isn’t what these fluoride sources describe, so for a sensitive plant, change the water instead of waiting it out. Our brown tips guide walks through the symptoms.
Which Filters Remove Fluoride?
Here’s where a lot of plant owners get tripped up. Nebraska Extension says activated carbon filters will not remove fluoride. They also won’t remove nitrate, bacteria, or the calcium and magnesium that make water hard. If your filter is a carbon filter, it’s not solving a fluoride problem.
These treatments do remove fluoride: activated alumina filters, distillation, reverse osmosis and ion exchange. It’s also worth checking any device’s claims with NSF (the National Sanitation Foundation) or the Water Quality Association before you buy.
Which Plants Are Fluoride-Sensitive?
- Dracaena, including the corn plant. Clemson Extension says dracaena is very sensitive to fluoride, with yellowing of the leaf tips or margins or dead, scorched areas. More in our guide to Dracaena fluoride toxicity.
- Spider plant (Chlorophytum comosum). It is listed as fluoride-sensitive, and chlorine and fluorides in tap water can cause leaf tip burn. It is a top indicator of fluoride, showing spotted leaves or burned tips, and University of Maine Extension says minute amounts of fluoride added to public drinking water can cause tip burn.
- Peace lily (Spathiphyllum). Brown leaf tips from fluoride toxicity are common in Spathiphyllum, and peace lily is among the most vulnerable houseplants.
- Yucca and Tahitian bridal veil (Gibasis pellucida), which are also listed as fluoride-sensitive.
For these plants, start with a growing medium free from perlite, since perlite contains fluorides, and water only with rainwater or distilled water. Keeping the soil pH between 6.0 and 6.5 helps keep fluoride from injuring dracaena. Water from a reverse-osmosis unit is another option, since reverse osmosis is among the treatments that remove fluoride.
Carnivorous Plants: Rainwater or Distilled Water
Carnivorous plants are where the advice gets firm. NC State Extension says to irrigate the Venus flytrap with rainwater or distilled water, because treated (chlorinated) water or hard water can kill the plant. If your Venus flytrap is turning black, the water is one of the first things to check.
Hard Water and Softened Water
Is hard water bad for plants? Not by itself. Hard water contains large amounts of calcium and magnesium, which are plant nutrients. Over time, though, salts can collect in a pot. A whitish residue on top of the potting mix means it should be flushed with clear water.
Softened water is the real problem. Home softeners exchange the calcium and magnesium in water for sodium, and over long periods sodium becomes toxic to plants and breaks down soil structure, which reduces drainage. Never water houseplants with water that has passed through a water softener, and don’t use softened water continuously on potted plants.
If your home has a softener, fill your watering can from a tap that bypasses it, or use rainwater or distilled water.
Distilled Water Has No Plant Food
Since distillation strips out minerals, a houseplant that gets only distilled water depends on fertilizer for its nutrients. Either an organic or inorganic fertilizer, or a combination of both, is a satisfactory source of nutrients for houseplants. Follow the label rate for the fertilizer you use.
Extension sources recommend distilled water for the most fluoride-sensitive plants and for Venus flytraps. Keep feeding your houseplants, but not the flytrap, which should not be fertilized.
Rainwater and Melted Snow
Free water from the sky is a great option. Rainwater and melted snow are excellent water sources, and rainwater, distilled water or melted snow at room temperature is recommended for Christmas cactus to prevent a buildup of mineral and soluble salts.
How to Make Distilled Water at Home
You can, but it’s slow. Here’s a simple stovetop method:
- Fill a pot halfway with water.
- Tie a cup to the handle on the pot’s lid so the cup hangs right-side up when the lid is upside down. Make sure the cup isn’t dangling into the water.
- Put the lid on upside down and boil the water for 20 minutes.
- The water that drips from the lid into the cup is distilled.
The pot, lid and steam get very hot, so use oven mitts, and let the water cool to room temperature before you use it on plants.
Distillation takes longer to produce water than other treatment methods, distilling units can be expensive to operate, and how long distilled water is stored can affect its quality. For a few houseplants, a jug of store-bought distilled water or a rain barrel is the easier route.
Quick Summary: Distilled Water for Plants
- Distilled water is safe for plants, but it has no nutrients, so keep fertilizing (except Venus flytraps)
- Many houseplants do fine on ordinary tap water
- Dracaena, spider plant, peace lily and other fluoride-sensitive plants do better with rainwater or distilled water
- Letting tap water stand removes chlorine, not chloramine or fluoride
- Activated carbon filters don’t remove fluoride; reverse osmosis, distillation and activated alumina do
- Don’t water houseplants with softened water
- Venus flytraps need rainwater or distilled water
What do you water your plants with: tap, rain or distilled? Tell us in the comments!
Frequently Asked Questions
Is distilled water good for plants?
Yes, it’s safe, but most houseplants don’t need it. Ordinary tap or well water is usually satisfactory for plants. Distilled water helps most with fluoride-sensitive plants such as dracaena and spider plant, and with carnivorous plants like the Venus flytrap. Because distillation removes the minerals in water, keep fertilizing houseplants that get only distilled water, though a Venus flytrap should not be fertilized.
Does letting tap water sit overnight make it safe for plants?
Only for chlorine. Chlorine can be removed by letting filled watering containers stand overnight. Letting water stand does not remove fluoride, and letting water sit at room temperature does not remove monochloramine, which some cities use instead of chlorine. For fluoride-sensitive plants, use rainwater or distilled water. Our brown tips guide explains the symptoms.
Which plants are sensitive to fluoride in tap water?
Dracaena and spider plant are the classic cases. Dracaena is very sensitive to fluoride, and the corn plant, spider plant, yucca and Tahitian bridal veil are all listed as sensitive. Fluoride tip burn is also common in peace lily (Spathiphyllum). Watch for brown or yellow leaf tips and margins.
Does a water filter remove fluoride?
It depends on the filter. Activated carbon filters will not remove fluoride, although they can remove chlorine and chloramines. Activated alumina filters, distillation, reverse osmosis and ion exchange do remove fluoride, and it’s worth checking a device’s claims with NSF or the Water Quality Association before buying one.
Can I water plants with softened water?
Not on a regular basis. Never water houseplants with water that has passed through a water softener. Softeners swap the calcium and magnesium in water for sodium, and over long periods sodium becomes toxic to plants and breaks down soil structure. Use a tap that bypasses the softener, rainwater or distilled water.