Over the years, I've read a LOT of gardening books. Some of them I use regularly, some infrequently. I've grouped them by type of book. Annotations coming soon.
Books about Gardening in Minnesota and Wisconsin
Minnesota Gardener's Guide, Melinda Myers
Birds of Minnesota and Wisconsin, by Janssen, Tessen, and Kennedy
The Midwest Gardener's Book of Lists, by Susan McClure
Weeds of the Northern US and Canada, by Royer adn Dickinson
Reference Books
Botany in a Day—The Patterns Method of Plant Identification, by Thomas J Elpel
Gardening Month by Month, by Martha Stewart
Illustrated Guide to Gardening, by Reader's Digest
The Book of Outdoor Gardening, by Workman Publishing
Design Books
Garden Style, by Penelope Hobhouse
A Garden for all Seasons, by Reader's Digest
Books about Particular Garden Types
Country Flowers -- Wild Classics for the Contemporary Garden, by Rob Proctor
The Cottage Garden, by Anne Scott-James
The Decorated Garden Room, by Tessa Evelegh
The Romantic English Garden, by Victoria's Secret
How To Books
Step-by-Step Landscaping, Better Homes and Gardens, Meredith Publishing
Step-by-Step Successful Gardening, Better Homes and Gardens, Meredith Publishing
The Big Book of Gardening Skills by the editors of Garden Way Publishing
The Complete Backyard Planner -- Hundreds of Ideas to Help Homeowners Make the Most of Their Homes, by L. Donald Meyers
Just for Fun
Miss Rumphius, by Barbara Cooney
Flower Confidential -- The Good, the Bad, and the Beautiful, by Amy Stewart
Wicked Plants -- The Weed that Killed Lincoln's Mother & Other Botanical Atrocities, by Amy Stewart
Currently Not Classified
Bloom and Blossom -- The Reader's Guide to Gardening, edited by Mary Swander
Great Gardens from Everyday Plants, by Anne Halpin
Little Herb Gardens -- Simple Secrets for Glorious Gardens - Indoors and Out, by Brennan and Luebermann
Rodale's Successful Organic Gardening -- Perennials, by Rodale Press