|MadSci Network: Botany|
I doubt that a low concentration of food coloring in the irrigation solution would affect plants. Food coloring is often used by students to show water movement in cut flowers or celery stalks. The food coloring can easily enter the cut flowers or celery stalks because the flower stem and celery petiole has been cut. In plants with intact roots, food coloring will probably not be absorbed by the plant. You might wish to try the experiment and see. References Re: If I water plants with colored water will it change the color of the plant?
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