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Q & A: Radishes

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Most recent answer: 10/22/2007
Ok, I’m doing this big science fair project and I need to know an answer to this question and I’ve looked everywhere! Ok here it is: the project that I’m doing has to do with adding food coloring and water to radish plants in little cups and comparing their growth to radish plants fed with water only. I need to know if there has ever been an experiment done like this before and if so, what where his/her results? Thank you!
- Lindsay Jackson (age 14)
Tri-North, Bloomington, IN USA
Lindsay -

I'm not familiar with any specific experiments that have been done on this. (But that doesn't mean that no one has done it.) In theory, the food coloring should have no effect on how the plant grows. But because of what's called "capilary action," the food coloring will be sucked into the plant right along with the water. This means that the plant should appear to be the same color as the food coloring. You may find it interesting to slice the radishes open afterwards. You should be able to see the locations of the tubes that the plant uses to draw water into itself because they will be colored. (You can see this even better with celery.)

For more information on the effects of food coloring (and other things used in food) on the growth of plants and animals, you may want to try contacting the (food and drug administration). They're in charge of making sure that anything used in food won't hurt people, so they may have more information on the testing that was performed to prove that food coloring is safe to eat.


(published on 10/22/2007)

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