The Best Type of Water to Wet Your Plants

“Water, water, everywhere, nor any drop to drink!” -Samuel Taylor Coleridge

When it comes to our plants, we not only worry about over- and under-watering, we worry about the kind of water we give them. Does tap water cause browning leaves? Should you try rain water? How about water from your fish tank? Let’s take a quick look at our water options!


Tap: We talk about tap water a lot in the House Plant Hobbyist Facebook group. While it is OK to give most plants, some are too sensitive and will be damaged by the chemicals in the water. A lot of people say to let the water sit overnight to help purify it through evaporation, but this is not fully true. Evaporation occurs, but that’s the water itself (and chlorine) evaporating, which can cause the rest of the chemicals, like chloramine, to become even more concentrated in the water. You can water plenty of plants with tap, but it may be worth checking out your local annual water quality report before giving it to your more sensitive plants.

Distilled: Distilled is basically dead water, which means everything in it has been removed through boiling. The pure water becomes steam, which is collected and voila — there’s your distilled water. That means that the contaminates, like the chemicals and heavy metals, are removed, as are the healthy minerals. Trace amounts of contaminants can still be found, especially if the water came from a source like farm runoff. If you’re distilling your own water from your tap, those types of contaminants shouldn’t be an issue. So, yes you can use distilled water to give your plants, but the good minerals that help keep the plant healthy and growing have been removed.

Rain/Melted Snow: Rain is by far the best type of water that you can give your plants. It is full of minerals that are necessary for plant growth, and will make your plants grow bigger and healthier than any other type of water. This is kind of a no-brainer, since the same plants that you grow in your house also generally grow wild someplace and are watered with rain!


Fish Tank: Aquarium water is amazing! It still isn’t as good as rainwater, but it is definitely good stuff. You’re taking tap water and using a water conditioner that will remove the bad stuff and you’re using water that has small amounts of animal waste, which means that it is a very mild fertilizer. Sometimes people worry it will smell bad, but it really doesn’t smell when you water from your fish tank in our experience, so you shouldn’t have to worry about that.

Spring: You know how I said rainwater is the best stuff you can give plants? Well, this is a close second. Since it comes from a natural source, just like rainwater, it doesn’t have any added chemicals in it that can cause your plants to not flourish as well as they could. I’m talking natural spring water, not the bottled stuff you can buy that has been purified or distilled.

Purified: This is basically distilled water that has had an extra step added, so the water has nothing it in besides that familiar chemical formula of two hydrogen atoms and one oxygen atom. Yes, water. I know, it is weird to think that the water all around us has stuff in it, but it does. Unless that water is purified.

R/O Water: R/O, or reverse osmosis, is a technique that is used to remove minerals and impurities from water, such as chloramine, salts, and heavy metals. This is fine to give to plants, and some prefer it because it lacks certain minerals that can cause issues with fertilizers. The downside to this is that the water lacks all nutrients, so it is really important that you make sure you are using a well balanced fertilizer.

R/O Waste: This water is not suitable for human consumption because it is the waste water that contains all of the chemicals and such that are removed. That means the chloramine, salts, heavy metals — you know, all of the bad stuff we filter out that plants don’t like. The good minerals are also in there, but they are concentrated like the chemicals.


Softened Water: If you have hard water and use a water softener on it, you might want to refrain from giving this to your plants. The salts that are used to do this aren’t good for plants and can actually hinder their growth.

Sugar or Salt: No. Just do not do this at all. Adding either of these to the water that you are going to give to your plants is just a terrible idea and will only make things go downhill. If you notice a white crust building up on the top of your soil, you may have water that’s too high in sodium, and that’s a bad thing for your plants. Sugar can attract bugs and help mold grow, neither of which are good.

If you’ve got questions about what kind of water, how much water, or how often to water, head over to HPH on Facebook and ask the community!