Discoveries in the Garden

review by Richard Robinson
Gardeners are experimentalists—we try new varieties, push the limits of weather, till or don’t. We observe, try something new, and observe again. Any gardener who has been at this a while accumulates a pretty large store of knowledge about the what, when and where, but less of the why. We learn that peas need a tight trellis to climb, while beans will gladly climb a straight pole. But why the difference? We know that topping a Brussels sprout plant will promote heavier sprouts, but why?

James Nardi, a research scientist at the University of Illinois, has written a book to help curious gardeners ask and answer some of their own “why” questions about phenomena they observe in the garden. The book includes large amounts of plant anatomy and physiology, a good number of classic plant biology demonstrations and experiments, line drawings that explain how to set up the experiments, and micrographs to show what’s going on at the cellular level.

There are chapters on seeds, plant organs and growth habits, development, photosynthesis, movements, ecology, and more. Each chapter includes a set of directed observations and suggested hypotheses that are explored through experiment, along with a fairly hefty bit of explanation that would not be out of place in a college course.

Indeed, if you took a botany or plant physiology course in college, much of this is likely to look familiar: corn seeds glued to filter paper demonstrates the geotropism of roots; a plant in an enclosed jar replenishes oxygen, allowing a candle to continue burning. This is not a criticism—these demonstrations are classics because they provide lessons about plant behavior that are both accessible and powerful.
However, that familiar content has not been adapted for best use by the home gardener. Instead, the book seems to be drawn pretty directly from a college lab course, without considering how it might be modified to fit the curious gardener outside the lab. The book describes experimental set-ups using “a 100 millimeter petri dish” and “filter paper,” without any recommendations for alternative materials more easily found at home. An experiment on the effect of light on germination calls for tobacco seeds, of all things. Similarly esoteric materials are specified in other experiments, with no suggestions for sources or substitutes.

This is doubly frustrating since such replacements exist, and such a list might have easily been generated in a couple of hours. The lack of such a list I think underlies a more general criticism—despite how it is positioned, this book has not been written with the home gardener specifically in mind.

Nonetheless, if your plant phys course is only a dim memory and you are looking for a refresher, or you are a neophyte to the world of academic botany altogether and want to get up to speed, this book might provide a painless and entertaining guide to a pretty serious chunk of the curriculum. The writing is lucid and logical, and the experiments, if you can find the right materials, are well described and would be fun to carry out.