Of course! Punctuation [i]should[/i] be a part if the poem.
A poet should never underestimate the power of punctuation. A dash, a comma, a colon ... and ellipse.. parenthesis, they all carry meaning and add to the power of the words they enclose. They are responsible for the flow of the poem, the breaks, the sighs, the breaths, the anticipation, the proclamations, the questions, and endings.
Every good poet will use punctuation properly to help establish the flow of the poem.