Elizabethan theater often used plant imagery to describe the health of a nation: gardens, for instance, play a major role in Richard II. Marlowe also draws on this symbolism in Edward II, often tying it to descriptions of Edward himself, as when the nobles describe Spencer Junior as a “putrefying branch / That deads the royal vine.” The rationale behind this and similar passages lies in Edward's own symbolic function as a monarch whose circumstances represent the circumstances of his entire country. Thus, in allowing social-climbing “flatterers” like Spencer and Gaveston access to himself, Edward is (according to the nobility) destabilizing the entire country.
The fact that it is a “mower” who, after Edward has lost the final battle and hidden himself in a monastery, reveals Edward's whereabouts to the nobles supports this idea: just as he literally prunes hedges, the mower symbolically “prunes” England back into shape. That said, Edward's arrest does not, in fact, end up putting an end to the country's problems, and it's worth noting that Mortimer Junior, who assumes power as Lord Protector after Edward’s fall, at one point compares himself to “Jove's huge tree.” Since Mortimer would not be the lawful king even if Edward II were dead, his use of this imagery arguably hints at his own growing arrogance and corruption, and further implies that it is not until the rightful heir, Edward III, ousts Mortimer Junior that England again returns to natural health.
Trees and Vegetation Symbol Timeline in Edward II
