Here's some more 'food for thought' on vegetable poetry:
Word History: Andrew Marvell's "To His Coy Mistress" contains many striking phrases and images, but perhaps most puzzling to modern readers is one in this promise from the speaker to his beloved: "Had we but world enough, and time . . . /My vegetable love should grow/Vaster than empires and more slow." One critic has playfully praised Marvell for his ability to make one "think of pumpkins and eternity in one breath," but vegetable in this case is only indirectly related to edible plants. Here the word is used figuratively in the sense "having the property of life and growth, as does a plant," a use based on an ancient religious and philosophical notion of the tripartite soul. As interpreted by the Scholastics, the vegetative soul was common to plants, animals, and humans; the sensitive soul was common to animals and humans; and the rational soul was found only in humans. "Vegetable love" is thus a love that grows, takes nourishment, and reproduces, although slowly. Marvell's 17th-century use illustrates the original sense of vegetable, first recorded in the 15th century. In 1582 we find recorded for the first time the adjective use of vegetable familiar to us, "having to do with plants." In a work of the same date appears the first instance of vegetable as a noun, meaning "a plant." It is not until the 18th century that we find the noun and adjective used more restrictively to refer specifically to certain kinds of plants that are eaten.