Written in the first person, "Weed" is about a speaker who feels deeply alone and unworthy. They see themselves as their own downfall, and they compare themselves to trees, bees and small insects, all of which seem prettier and more welcome than they are. The wish that follows is a sad one: to be a weed, tucked away in a crack, swaying in the wind, unseen and untroubled.
Then the poem turns. The speaker realises they may already be a weed, and that this could explain the loneliness, since nobody wants a weed in their garden. Even the image of growing "in the stones" offers no comfort, because the speaker still feels unwanted. The final line, "It would have been best if I'd never grown," is the bleakest moment, and it reads as a wish never to have existed.
The mood is quiet, heavy and self-critical. The short, plain wording makes the sadness feel raw and honest rather than dressed up.