As a Romantic novel, The Scarlet Letter borrows elements of its Gothic sub-genre to accentuate the enigmatic nature of all the characters of the novel. The supernatural conception of Pearl, the elements of fate that accompany the life of Hester Prynne, and the similarly-supernatural nature of Arthur Dimmesdale (or at least how people view him), all enhance the symbols presented throughout the novel.
The cemetery, a central location that consistently reminds the villagers about the finite nature of life, was plotted in the village at the same time as the prison. No matter how optimistic the villagers may have been about the new land, they cannot get away from the reality that we are all still human and, as such, things will happen. People will die, because it is a law of nature; people will break the law, because it is human nature. Similarly, the prison (and the scaffold nearby) remind us of the weaknesses of the flesh, the tendency of humans to stir from the right path, and the need for consequences.
The wild rosebush in the prison has a meaning of its own. Hawthorne describes that it has, actually, multiple meanings. It stands for resilience, as it strives and continues to grow despite of being overshadowed by the oak trees nearby. It has maintained its color and uniqueness despite its location. Hence, the rosebush could be either Hester or Anne Hutchinson herself, to whom Hawthorne likens.
...there is fair authority for believing, it had sprung up under the footsteps of the sainted Ann Hutchinson, as she entered the prison-door,—we shall not take upon us to determine.... It may serve[...]to symbolize some sweet moral blossom, that may be found along the track, or relieve the darkening close of a tale of human frailty and sorrow.
While the rosebush, bright and beautiful, colors the horrid prison door, the weeds of the land are Chillingworth's tools of occupation. He places particular importance on the black weeds that he finds in the cemetery, which he uses to bother Arthur Dimmesdale in order to taunt him to confess what all is bothering his heart. The black weeds are supposed to be the only evidence of anything ever missing the heart of the dead man that lays beneath it. As such, Dimmesdale's own dark secrets might one day surface in the same fashion. This is what the meaning of those weeds really is.