WHAT FLORIDA NATIVE PLANT IS BLOOMING TODAY?: CLIMBING HEMPVINE (Mikania scandens)
Photo depicts Buds. Can be a Larval host for Little Metalmark Butterfly (Calephelis virginiensis)
Nectar Source, showy flowers, heart shaped leaves. Low Growing vine that will climb a fence but doesnt provide deep coverage as other vines might. Dies back.
Native American Ethnobotany for this genus: http://naeb.brit.org/uses/search/?string=Mikania+scandens
In Bloom from Sept 2011: