pole bean vs bean plant

pole bean and bean plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
pole bean	Yes	No	No	No
bean plant	Yes	No	No	No

As nouns, bean plant is a hypernym of pole bean; that is, bean plant is a word with a broader meaning than pole bean:

pole bean: a climbing bean plant that will climb a wall or tree or trellis
bean plant: any of various leguminous plants grown for their edible seeds and pods

Other hypernyms of pole bean include bean.

pole bean (noun)	bean plant (noun)
a climbing bean plant that will climb a wall or tree or trellis	any of various leguminous plants grown for their edible seeds and pods