|MadSci Network: Botany|
When I get questions on using human beverages for irrrigating plants, I am reminded of the old comedy skit where a person believes they have been given a poisoned beverage and secretly pours it into a potted plant. The plant immediately wilts. Although unintended, there is actually some science behind that scenario. A regular Red Bull brand energy drink contains 200 mg sodium and 27 grams of sugars per 8.3 fl oz. serving. A sugarfree Red Bull contains 200 mg sodium and 0 grams sugar per serving. One fl. oz. is 29.6 ml so both contain 814 mg sodium per liter. That is an excessive amount of sodium for an irrigation water. The sugar concentration would be 110 grams sugar per liter. That is also a high level for a plant. Both the sodium and sugar will make water less available to the plant. The sodium can also be directly toxic to the plant. Plant roots can absorb water from the soil solution by osmosis because their cells contain more dissolved subtances than the soil solution. Irrigating a plant with Red Bull would greatly increase the soil solution concentration and make it difficult for the roots to absorb water. The various vitamins and other ingredients, such as taurine, in Red Bull could not be used by the plant. Photosynthetic plants make all their own vitamins and organic compounds. The best "beverage" for plants would be a fertilizer solution, such as Miracle Gro. It would also be a lot cheaper to irrigate plants with a fertilizer solution than an energy drink. See the last two references for more details. References Red Bull Ingredients Re: What is a good plant to test the effects of sugar or sweetener? Re: Why did the liquids kill the plants? Why did the tea do well?
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