Thank you for contacting BibleAsk.
Vegetables were not part of the Eden diet “And God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every tree, in the which is the fruit of a tree yielding seed; to you it shall be for meat” (Genesis 1:29). We learn from the divine record that man was to eat of the products of both field and tree, in other words of grain, nuts, and fruit. The animals were to eat of “every green herb,” which are vegetables, green plants, and grass.
Vegetables were added later to the diet of man after sin. God said to man, “and thou shalt eat the herb of the field” (Genesis 3:18). The divine punishment after sin provided also a partial change in diet. We evidently are to conclude that the quantity and quality of grains, nuts and fruits originally given to man were, as a result of the curse, reduced to such an extent that man would be required to look to the herbs for a portion of his daily food.
This change in diet may also have been due in part to the loss of certain elements from the tree of life, to a change in climate, and perhaps most of all to man’s sentence to hard labor in the process of earning a livelihood.