Houseplants are a wonderful source of calm and natural beauty. They bring endless amounts of joy to indoor gardeners.
In order to meet their full potential, houseplants need a quality water source. But what is the best water for indoor plants?
Should you use tap water or distilled water? Is filtered water better or should you only let your plants drink from high end bottled water? And, how often and how much do your plants need their H2O fix?
You have probably had some or even all of these questions come up in your quest to give your plants the best water possible.
Best Water For Houseplants (The Answer)
In our experience the best type of water for your houseplant is rainwater. Natural spring water and aquarium water are also great options for watering your indoor garden. All 3 are full of minerals, lack chemicals, and have better oxygen availability than other sources of water.
We’re about to discuss every common form of water available for your indoor garden.
While we give our recommendations for the best water for optimal plant health, it’s up to you to decide what works for you and your plant babies.
Keep reading to find out why we love rainwater, spring water and cast off aquarium water (and to find out which sources of H20 aren’t the best!).
Learn how to water snake plants here.
Why Is Rainwater Good For Indoor Plants?
Rainwater is full of natural minerals that your plants crave, and it lacks the toxic chemicals found in tap water. It also delivers the highest amount of oxygen to the roots, which is essential for absorption of minerals and water. Adequate oxygen to plant root cells results in a healthy, thriving plant.
And let’s face it, rainwater is what your houseplant would naturally receive in it’s native habitat! Most houseplants are tropical plants. They are used to receiving deep soaks in humid jungles.
Houseplants not only need hydration from their water source, they also rely on water for healthy nutrients and minerals that promote plant growth. Rainwater supplies both hydration and nutrients for the plant, and has a neutral pH, helping to neutralize the pH of the soil.
The nitrates in rainwater promote vibrant green growth for your plant, and there are no toxic chemicals such as chlorine or fluoride.
The kind of water certainly matters…. most plants don’t appreciate tons of chemicals in their drink (who does, after all?).
Most of us aren’t lucky enough to live in a rain forest, but we can gather our own water using rain barrels, and bring it on indoors.
Different Types Of Water For Indoor Plants
We’ve established rainwater as a clear winner for watering indoor plants, but what other options are there? Let’s dive in. We’ve rated each water source on quality and are showing you the easiest ways to access each!
Keep reading to learn all about the different types of water available for your houseplant and scroll to the end of the post for some watering tips that will help your plants stay healthy and strong.
Tap water may seem like an obvious choice for watering plants, but it is a good idea? City tap water comes straight to the home from a water treatment plant, where it is treated with chlorine and fluoride, making it “ideal” for human consumption.
All treated tap water contains chemicals and heavy metals, and these chemicals can damage plants.
Fluoride, for example, is a common additive for city water.
According to Plant Pathology from OSU, fluoride is an accumulative poison to plants and their foliage. Spotted leaf tips are usually the first sign of damage.
Chlorine damage is common in tap water as well and will often be evident by the brown tips on the end of plants.
Spider plants, Corn plant, African violets, and Dracaena are a few that are particularly susceptible to damage from chlorine and fluoride.
Making Tap Water Safer (De chlorinate)
Some houseplant enthusiasts recommend letting tap water sit for 24 hours in order for the chemicals, such as chlorine, to dissipate.
When set out, it can take 1-5 days for chlorine to dissipate. You can speed up the process by boiling the water.
Filtered Water For Plants
Filtering tap water removes the toxic chemicals found in regular tap water and is a great option for your houseplants.
Using a water filter on your tap improves the water quality by removing chlorine, lead, and other chemicals. Make sure to use a reputable, well rated filtration system (there are many options on amazon that fit a wide array of budgets).
Overall, we do not believe tap water is the best source of water for indoor houseplants (is it even good for human consumption?!).
But if you do use tap water, use a filter to remove most of the chlorine, fluoride and other chemicals (this is beneficial for animals and people, as well!).
Well water may seem like a great option for giving houseplants a deep drink.
However, well water is often a hard water source that leaves limescale deposits on pipes and water fixtures. The excess minerals in hard water can cause problems for houseplants, and the treatment of the hard water build up can also cause problems.
Hard water is often treated with a water softener to “soften” the minerals. Water softeners contain high levels of salt, as the sodium ions replace the hard minerals in the water.
This salt level, however, is detrimental to indoor plants.
We speak from experience when we say soft water is not good for indoor plants! My mother moved into a beautiful home in the countryside, complete with it’s own well water. She had just started her houseplant addiction (er journey) and had a small indoor garden. Without realizing it, she killed all her plants with the water softened well water! (Not to worry: she quickly learned and has a thriving sun room filled with healthy houseplants today).
Water softeners contain high amounts of sodium, which will build up and eventually harm and even kill your plants. (Spider plants and peace lilies are especially susceptible.)
Rain Water (Or Melted Snow)
As stated above, we believe the pure water source of rain or snow is the best way to water houseplants.
Houseplants are living organisms that originate from a wild location. They are used to garnering moisture, oxygen, and some of their nutrients from the rain.
Rainwater contains potassium and magnesium ions, calcium, and nitrates which are essential for helping plants develop lush foliage. It also contains the best oxygen content of any water source. This high oxygen level helps plant absorb nutrients into the root zone.
The most common way to collect rain is to use a rain barrel. People often create their own as well (see this awesome video for inspiration).
Rainwater (or melted snow), is a free source of water that you can use to water both indoor and outdoor plants.
The downsides to rain water:
-When living in a highly populated or industrial area the water quality may be less than desirable. The rainwater may be filled with toxic chemicals and may not be a great way to water your plants.
-Dry areas that receive little rainfall will not be a good fit for water collection. Rainwater is not the best option in these areas.
Distilled water has been boiled so that it turns into a water vapor. It is then condensed back into a liquid.
The distillation process removes everything from the water, both minerals to harmful chemicals. At first glance, distilled water seems like it may be a great choice for watering plants because it lacks the harmful chemicals that can be detrimental to houseplants.
Distilled water also lacks vital nutrients your plant needs to thrive, however.
We look at distilled water as a neutral watering option. It’s not harmful to your houseplants, but if a better option such as rain water or spring water is available, use that instead!
Fish Water (Used Aquarium Water)
Rich with nutrients, fish tank water is an excellent source of water for houseplants.
Fish improve the water quality when they go poo in the water (funny, but true!). Their excrement is rich in nutrients and minerals that plants can use to thrive.
One of the main nutrients is Nitrates which helps the plant to grow healthy foliage. Using aquarium water is also a good way to recycle water!
You may be wondering if used aquarium water stinks. In our experience we have not noticed fish tank water causing odor issues.
A caveat: you do not want to use salt water from a fish tank to water your houseplants. Salt water will dehydrate your plants and eventually kill them.
Natural Spring Water
Natural spring water, either bottled or collected from a local spring, is an excellent source of water for indoor plants.
Spring water is rich with healthy minerals that can be easily absorbed by the roots of the plants. Spring water also has a high oxygen content, making it a great choice for nutrient delivery.
You can easily purchase natural spring water from a grocery store, but if you’d like to go the natural route, you can find a natural source of spring water using this website.
Learn how to care for peace lily so they bloom here.
Reverse Osmosis (RO system)
Reverse osmosis water has been cleansed of chemicals by pushing the water through a semi permeable membrane. A reverse osmosis system can remove up to 99% of all toxins and chemicals in the water.
Reverse osmosis also removes minerals your plants need from the water. Nitrogen, potassium, magnesium and calcium are just some of the crucial nutrients that will be removed. Like demineralized water, RO water
won’t hurt your plant, but lacks the necessary nutrients for a thriving indoor garden.
Because of this, we do not recommend reverse osmosis water as a long term watering method for your houseplants.
Now that we’ve discussed some of the most common watering options, let’s explore some important aspects of watering your plants and troubleshoot some common problems!
What Do Houseplants Need From Their Water?
Does the water you give your houseplants affect their health? Yes! As we mentioned above, plants water for more than just a good drink.
Hydrating a plant with a good water source allows the proper amount of oxygen to reach it’s roots.
Plants absorb much needed nutrients through the water, and the water helps to balance the pH of the plant’s soil. Water is also crucial for photosynthesis, allowing the plant to create energy in the form of glucose.
Cold Or Warm Water For Houseplants?
Houseplants love tepid or room temperature water.
While humans may crave an icy cold glass of water, giving our houseplants the same can actually shock them. This can result in stunted growth or even confuse the plant into thinking it is in a colder season.
Remember that the warm and humid natural environment of houseplants offer rani of mild temperatures, not cold downpours.
For the health of your plants, make sure you use tepid or warm water when watering your indoor plants, and skip freezing them out with cold water.
Should You Add Sugar Or Salt To Houseplant Water?
No, you should not add sugar and/or salt to houseplant water to increase growth and vitality.
There are some common myths that sugar and salt can be beneficial additives when watering houseplants. We’ve seen that increased salt can be detrimental to plant health. Adding sugar can cause the plant to rot and attract insects.
If you want your plants to grow bigger and stronger, stick with quality water, enough light, proper soil and occasional fertilizer.
Common Problems From The Wrong Water Quality
Some common problems from using the wrong water source for your plants:
- Salt in softened water can kill plants
- Hard water can cause a build up of minerals in the soil over time. This can cause the leaves of the plants to burn and eventually kill the plant. Signs of leaf burn are brown or yellow leaves, dark brown spots, and curled leaves.
- Lack of nutrients in the water can also be a problem. Stunted leaf growth, yellowing leaves, or abnormal coloring such as purple/red tones to a leaf can be indicative of lack of minerals.
Best Ways To Water Your Plants
There are several different ways to water houseplants.
Some people like to use a self watering container that waters the plant from the bottom.
We believe it’s healthier for the plant to apply water from the top of the soil line, giving the plant a deep soak. This ensures that the minerals in the water and soil are evenly distributed and reach the roots of the plant.
You can also give your plant a lukewarm shower from time to time. This mimics the rainfall in it’s natural environment and increase humidity levels.
How Often + How Much To Water Houseplants (General Guide)
Each indoor houseplant will have different watering needs. Some houseplants, like Snake plants and succulents need very little water to survive. Others, like poinsettias, prefer to be watered every week.
Your plant’s requirements for water come down to a few factors including the humidity in the air, the type of plant, and it’s natural requirements for water.
These guidelines will help you figure out how much water and how often to water your plants:
- Type of plant and where it originates from
- How humid or dry your environment is
- Size of the plant and what kind of container it is growing in (larger plants typically require more water)
- The season (the time of year can affect air temperature and humidity)
- What region you live in (the region you live in will affect the humidity + sunlight).
- Soil: what type of soil is being used and how it drains and retains moisture
Research your plants and figure out what works best for your indoor houseplant in your environment!
Houseplant Watering Tips + Tricks
Each individual houseplant has unique watering needs. However, these houseplant watering tips and tricks offer some helpful general guidelines:
- Oftentimes plants will help you when you are thirsty. For example, when a Peace Lily’s leaves droop she is thirsty, and in fact she perks right up and recovers when watered.
- The soil surface is often a good indicator of moisture in the plant. Go ahead and stick your finger into the soil a few inches to see if the soil below the surface is still moist.
- Soggy soil is typically not ideal for any houseplant and can encourage rot and attract fungus gnats. Good drainage is always a must!
- Over watering is one of the most common ways a houseplant is killed. When in doubt, start giving your plant less water.
- A drainage hole is essential for proper watering. If no drainage is available for your plant, root rot will set in and eventually kill your plant. Root rot decays the root of the plant and causes disease. It also encourages pests!
- Some plants are extremely hardy when it comes to watering and others will we put under the category of “sensitive plants”. Plant care truly varies, so don’t be afraid to pick and choose plants to find what works in your life.
- Always allow excess water to seep from the bottom of the pot. You’ll know your plant has enough water when you see the water draining.
- Typically speaking, give a houseplant a deep soak when watering. It’s better to give a generous amount of water less frequently than to shallow water your plant and leave it’s roots craving more! Remember that different plants have different needs for both water and nutrient intake.
FAQ’s On Water For Houseplants
Yes, bottled water can be a great option for houseplants. Look for bottled natural spring water which will contain minerals.
The healthiest water for plants is natural rain water, spring water, and recycled aquarium water. These water sources don’t have chemicals, have a high oxygen level, and contain minerals.
Plants that are given natural rain water, spring water or used aquarium water receive the right water and nutrients to grow strong and healthy.