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The popular potted plant, Pothos aureus (or Epipremnum aureum) is happy to grow in a jar, with only water, for years. How is this possible when other plants need at least Nitrogen, Phosphorus and Potassium?

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  • $\begingroup$ Pothos needs those nutrients as well, but they are more tolerant of poor nutrition than most plants, therefore rendering them better houseplants (most people don't fertilize their plants properly). But with no nutrients, the plant will begin to fade. A good hydroculture system includes a nutrient solution, to keep the plant fed, and an aerator, to add oxygen to the root zone. $\endgroup$ – J. Musser Sep 24 '14 at 0:45
  • $\begingroup$ "Tolerant" is an understatement... the plant is putting on mass for years, without those nutrients at all. How is this possible? $\endgroup$ – Greg Bell Sep 25 '14 at 5:03
  • $\begingroup$ This is a good question but unfortunately you are making the false assumption that the water has no nutrients in it. Pothos probably is simply very efficient at extracting these nutrients from water. $\endgroup$ – James Feb 5 '15 at 0:24
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It is not possible, that a plant grows without any nutrients. Magnesium for example is needed in every chlorophyll, so there is no photosynthesis without magnesium. Another point is that plants can not get nitrogen from the air, so they have to get it from the soil and nitrogen is present in every amino acid, which build the plants proteins. Proteins are essential for every living organism. This are only two points and there are many many others why every plant needs nutrients like nitrogen phophorus, magnesium...

If it seems that Epipremnum aureum does only need water, maybe the plant gets its nutrients from a place you don't expect. Maybe the water is contaminated. Are there leafs falling into the water for example? Another possibility could be that Epipremnum aureum stored a lot of nutrients before it got only water but this won't last for ever.

I read your comment, thats why i think the nutrients have to come from the water. Additionally I found this publication about Calcium Deficiency Symptoms of Epipremnum aureum

I think you know that tap water or rain water isn't pure H2O. We just measured the tap water in Cologne, by ICP-MS. This is no official measurement, and we measured only once but I think its nice to see whats else in tap water. Unfortunately we couldn't measure nitrogen, because normally the machine is used for plant extracts and there would be to much nitrogen. barplot tap water cologne kalk Maybe your Epipremnum aureum gets enough nutrients from the water, I don't know if this is possible and how often you change the water.

Your pot could also be a source for nutrients if its not sealed up.

In conclusion the answer is that in general it is not possible, that your plant grows without nutrients. So there is a source which can be only detected by yourself, because you know the exact conditions under which your plant grows. I hope I could give you some hints.

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Tap water does contain a significant amount of metal ions in solution, and this applies to all water sources (rainwater, groundwater) with the exception of ultrapure (eg distilled or reverse osmosis water).

For example, the official analysis of the NYC water supply in 2015 shows that there are significant quantities of nitrogen, phosphorus and potassium in the tap water samples taken.

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In short, pothos does in fact require minerals to grow, and these minerals are provided by the water.

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    $\begingroup$ I owned a commercial soil/plant/water testing laboratory for 28 years, and have written 3 books on Tropical Foliage Plants, including Epipremnum (pothos). There are likely a lot more minerals in your water in that vase than you think there are, enough obviously to keep the plant alive and to some extent growing for years. I find nothing wrong in this answer. You will find small amounts of nitrates, sulfates, calcium, magnesium, boron and several other plant nutrients in most tap and well waters. My reference is 35 years of analyzing water samples; also refer to the book Groundwater and Wells. $\endgroup$ – Lynn Griffith May 9 '16 at 17:49

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