M ost gardeners know next to nothing about the physiology of plants. Often the only plant information we have is from the hang tag, and many times the tags have been inadvertently switched.

Ruth Kassinger suffered the guilt of murdering her kumquat tree while other plants receiving the same treatment thrived. How could that happen?

“A Garden of Marvels, How We Discovered That Flowers Have Sex, Leaves Eat Air, and Other Secrets of Plants,” published in 2014, is the result of researching the histories of famous botanists, seeking out contemporary agronomists and botanists and talking to farmers who are adapting some unique methods. She claims her hope was to become a better, “or at least a less lethal, gardener.”

Her quest for knowledge came from her desire to grow a “cocktail” tree in her conservatory where she was successfully growing other fruit trees. She had seen a multi-fruited citrus tree (oranges, tangerines, lemons, limes, grapefruits and kumquats) at Logee’s Greenhouse in Connecticut and wanted one.

In an attempt to purchase such a tree she discovered there were no nurseries in her home area of Maryland or Virginia that carried a cocktail tree. Finally, after calling the University of Florida Citrus Research and Education Center, Kassinger was given the name of a citrus nursery owner in Florida who could help. The owner agreed to turn a 6-foot Hamlin orange tree in a 35-gallon pot into her cocktail tree, but it would take at least 15 months. In addition, she would have to transport it herself because of government regulations. No UPS or FedEx delivery to the front door.

She wanted to better understand the grafting procedure and what the nursery owner was telling her. The research bug bit, and she has ended up educating and entertaining readers with her experiences.

Uncovering the fundamental facts of botanical science came much later than other sciences. Look at any growing plant material and you understand nothing of its workings. It has no mouth, no heart, no digestive system no muscles, no functioning body parts that are visible when dissected.

During the 17th century, no one understood what a plant was. Old myths and fables were still believed, such as barnacles that grew on trees hatched into geese; asparagus grew from crushed rams’ horns, and plants could birth animals atop their stalks. That people believed those myths seems comical now.

There were great debates and papers written as to the complexity of a plant. How does a plant take in food? Does it have a stomach? Aristotle believed roots took in food from the soil indiscriminately. Eighteen hundred years later, physician Girolamo Cardano concluded digestion took place in an area at the base of a plant’s stem or a tree’s trunk, just above the roots. Does sap circulate like the blood of an animal through a closed system? If it does, would it flow in one direction?

Kassinger writes of fascinating interviews with farmers, agronomists and botanists. The brake fern, for instance, was put to work removing arsenic from soil in Washington, D.C. A farmer in Ontario, Canada, was switching from coal and oil to burning miscanthus giganteus, an enormous and sterile hybrid grass, to heat his greenhouses. Farmers in Kansas are interested in trying to conserve water, topsoil and fertilizer by breeding deep-rooted perennial versions of annual grains.

The book gives much food for thought. I can’t help but wonder what agriculture will be like 20 years from now. With all the research and the new technology being developed there are probably many more garden marvels awaiting us.