We grow strawberries, black raspberries (not found at all in stores around here), red raspberries and peaches for fruit here. Lots of value returned for what we put in to it. Strawberries are out biggest, and we yield about 50-70 pounds each june. And we can pick all this fruit when it is ripe, rather than when it is "shipping-ready".
Herbs are another high-value garden item for us. During the warmer months most meals get a fistfull of fresh organic herbs, probably $5 to $10 worth if bought at the store. Oregano, basil, sage, thyme, rosemary, lemon balm, peppermint, spearmint, sorrel, nasturiuim, rosa rugosa, lavender, chives and more.
Spinach, lettuces and various greens are in the greenhouse in late winter/early spring, sometimes over-
winter. Much savings over store bought.
Tomatoes, potatoes, corn, beans, etc. in the main garden. The economics are less certain here...