In Natural Companions: The Garden Lover’s Guide to Plant Combinations (Stewart, Tabori & Chang, $40), naturalist and gardener Ken Druse offers a plenitude of planting suggestions. Two-page spreads with a brief essay by Druse and an image by artist Ellen Hoverkamp are interspersed with photographs of the plantings in action. The illustration at right accompanies an essay on flowering shade plants. Hoverkamp creates these portraits using a large flatbed scanner. In their variety of species and attention to composition, some of the images are reminiscent of Basilius Besler’s or Maria Sibylla Merian’s natural history illustration. The book itself has the packed-to-the-brim feel of those artists’ collections. And like its predecessors, Natural Companions reveals its concerns in part by what it omits: Information about the geographical origins of the species mentioned is not always given. I would find the portraits even more revealing if I could imagine the journeys their subjects had made in order to arrive on Hoverkamp’s scanner. Nonetheless, Druse scrupulously provides scientific names, and he emphasizes the value of planting species native to your region. He has made the wise decision not to include known exotic invasive species, such as Akebia quinata, that should be avoided in the United States. Species that are invasive in some U. S. regions but not others are marked with an asterisk. Druse and Hoverkamp have made a splendid book that will be useful to careful gardeners and armchair botanists alike.