There were 15 takes of Sissy Spacek slapping Marisa Tomei. The final version of the film used the first take.
The title refers to the rear compartment of a lobster trap known as the "bedroom" and the fact that it can only hold up to two lobsters, before the lobsters begin to turn on each other. When there are more than two lobsters, it is said that there is "trouble in the bedroom."
A scene cut from the final version shows Ruth (Sissy Spacek) and Matt (Tom Wilkinson) watching the film Barry Lyndon (1975) at The Strand Theater in Rockland, Maine on the night of their wedding anniversary. Ruth tells her son Frank (Nick Stahl) "It was the first film your father and I ever saw together." This was intended by director Todd Field as an homage to Stanley Kubrick, whom Field had worked with on Eyes Wide Shut (1999)
The poems quoted during Willis Grinnel's two poker parties are William Blake's "Auguries of Innocence" and Henry Wadsworth Longfellow's "My Lost Youth," respectively.
Henry Field: When Matt remembers his son climbing a tree as a child, the younger version of Frank Fowler is played by Todd Field's son.