Nearest book at hand: "Clinical Dermatology, An illustrated Textbook", by Rona M. MacKie, 3rd edition
"The leaves would be a sickly yellow instead of green, because plants use iron in synthesizing chlorophyll. (next page) Plants in general are made up almost entirely of compounds of carbon, hydrogen and oxygen - compounds that chemists refer to as organic, with no relation to the word used to designate foods that conform to the USDA's National Organic [Foods] Program. Minerals, on the other had, are the seventeen inorganic chemical elements that are essential nutrients for plants. "
Hmmm. Both seem pretty nerdy. Heavy on the Science, light on the Fiction.