You never outgrow baby vegetables: miniature carrots, melons, peppers, and other pint-sized vegetables are cute, sweet, and easy to grow.
Baby vegetables of all kinds have earned their places at summer picnics, where they are just the thing for grilling without chopping, and for snacks. They're a gourmet's delight on a dinner plate, and they charm children, of course, but midget vegetables are an unexpectedly fascinating crop. Many of them grow on relatively small plants, so they can easily be grown in pots.
Some crops, such as cucumbers and many root vegetables, can be picked at any stage of their growth. Tiny radishes, no bigger than a marble, are delightful in salads. Zucchini and beets can also be picked when they're quite small, but miniature varieties never get very large at all. 'Eight Ball' is an irresistible round mini zucchini; 'Little Chicago' beets grow to scarcely to the size of a golf ball, perfect for pickling or for salads. 'Peter Pan' pattypan squash are only two-three inches across: they are great on the grill.
You can find miniature varieties of just about any vegetable you can think of: prolific, sweet cherry tomatoes (round, grape, or pear-shaped) come to mind, but bok choi 'Toy Choi' only grows to about five inches tall: each plant is a single delicious serving. 'Caracas Hybrid' carrots are sweet and delicious, and they're only three inches long, you can eat a whole bunch. Snack-sized 'Golden Baby Belle' peppers can be picked when they're just an inch long; they're cocktail-party peppers.
'Sugar Baby' watermelons are eight inches across, and 'Baby Bear' pumpkins are kid-sized versions of jack o'lanterns.
Miniature vegetables are a good fit for small gardens because the plants can be spaced a little closer than their full-sized relatives. They're great in pots, too. Baby carrots or bok choi can be grown in a window box. 'Baby Bubba' okra is a small plant and looks pretty on a patio, but it eventually produces full-sized pods. You can let the pods mature at four inches long (it's a quick crop, just 53 days from seed), or pick the okras when they're just half-sized; at only two inches, you'll find they're full of flavor.