Here are my top three favorite gardening how-to books, in ascending order:
Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long by Eliot Coleman. Honestly my favorite book on not only extending your season, but making it possible to eat from it year round, in the north, without supplemental heat. I love Coleman's approach to gardening, and to solving the problem of how to have nourishing, nutrient-rich food even in the dead of Maine's winter.
The Garden Primer: Second Edition by Barbara Damrosch has a wealth of good general information on gardening practices, planning, and care. I'm going to plant a shrub border like the ones she details in here some day . . . Barbara shares her experience of years in landscape work, while keeping away from the toxic chemical fertilizers, et al, that are proving to be so unhealthy for both plants and people. (I grew up on a modern farm--complete with herbicides, pesticides, and fertilizers galore. I know that of which I speak.)
And my favorite book ever on vegetable gardening is Great Garden Companions: A Companion-Planting System for a Beautiful, Chemical-Free Vegetable Garden by Sally Jean Cunningham. (I saved the best for last.) She talks a lot about the needs for edible plants, what keeps them happy, and how to keep your garden as a whole healthy. (And, since she keeps chemical-free gardening at the forefront, it's highly self-reliant, as well.) Beautiful photography, open and accessible format, and to the point. There are garden plans, troubleshooting guides, and loads more. I <3>
So what are your favorite gardening books and websites? Do tell!