LAST week in Chelsea, Mich., as people wilted and vegetables flourished in the intense heat, Anne Elder ran through some of her favorite summer ingredients: pearly garlic “rounds” that flower at the top of the plant in hot weather, the spreading leaves of the broccoli plant, yellow dandelion flowers that she dips whole into batter and deep fries.

“When kids visit the farm, we give them cornstalks to chew,” she said. Like sugar cane, the stalks contain sweet juice.

For Ms. Elder, who runs the Community Farm of Ann Arbor, the edible vegetable begins with the sprouts and does not end until the leaves, vines, tubers, shoots and seeds have given their all.

If home cooks reconsidered what should go into the pot, and what into the trash, what would they find? What new flavors might emerge, what old techniques? Pre-industrial cooks, for whom thrift was a necessity as well as a virtue, once knew many ways to put the entire garden to work. Fried green tomatoes and pickled watermelon rind are examples of dishes that preserved a bumper crop before rot set in.