Vegetable Gardening, Or Olericulture, is the art of growing the crops which are commonly known as vegetables. The term "vegetable" is usually applied to the edible parts of herbaceous plants. With some fruits, botanically so considered, as watermelon, muskmelon, tomato and eggplant, the parts used as food are commonly called vegetables. While fruits are extensively employed for dessert without cooking, heat must be applied to most vegetables before they become palatable; notable exceptions are tomato, celery, onion, lettuce and melons. Vegetables of great commercial importance are asparagus, bean, beet, cabbage, carrot, cauliflower, cucumber, horse-radish, parsnip, pea, pepper, sweet corn, sweet potato, radish, spinach, squash and turnip. The potato is also a vegetable, but it is generally regarded as a field crop, and it is often included in rotations with grass and cereals.