Why are mushrooms, which are biologically distinct from plants, found in the produce section?

They are grouped there because they are similarly perishable, generally require refrigeration, and are typically sold raw and unprocessed.

Mushrooms, being fungi, belong to a biological kingdom separate from plants, yet their placement in the standard grocery store produce section is nearly universal. This placement is not based on taxonomic similarity to fruits or vegetables, but rather on shared physical and handling characteristics relevant to fresh goods. Specifically, mushrooms share the perishability profile of fresh produce, requiring climate-controlled environments like refrigeration to maintain quality. Furthermore, they are generally offered to the consumer raw and in a minimally processed state, aligning them functionally with the other items traditionally found in that department, even though their taxonomy differs fundamentally.