 Together with onion and celery, carrots are one of the primary vegetables used in a "mirepoix" to make various broths.The greens are edible as a leaf vegetable, but are rarely eaten by humans; some sources suggest that the greens contain toxic alkaloids.When used for this purpose, they are harvested young in high-density plantings, before significant root development, and typically used stir-fried, or in salads.