Lobelia amoena, commonly known as southern lobelia, is a species of flowering plant in the family Campanulaceae native to the southeastern United States.
Southern lobelia may be annual or perennial, and typically grows erectly with strict or freely branched stems. The leaves are elliptic to lanceolate in shape, measuring 4âÂÂ15 cm in length and 2âÂÂ4 cm in width. Leaf margins may be entire, crenate, or serrate. Inflorescences are terminal racemes that are often leafy and bracteate, giving the flowers an axillary appearance. The flowers are zygomorphic and bilabiate, with a 5-lobed calyx that is more or less actinomorphic. The corolla is 2-lipped and fenestrate, with the upper lip divided into two lobes and the lower into three. Sepals are entire or remotely glandular-serrate. The corolla tube is 7âÂÂ9 mm long, and the filament tube measures 5âÂÂ7 mm. There are five stamens, which are completely united. The fruit is a capsule, 6âÂÂ8 mm wide, and dehisces apically through pores. Seeds are yellowish-brown, oblong, tuberculate, and range from 0.6 to 1 mm in length.
Southern lobelia is found from western North Carolina and eastern Tennessee south through western South Carolina to central Georgia and eastern/central Alabama. There is also a disjunct population in the Florida Panhandle and along the coastal plain of Georgia and South Carolina. It grows in floodplain forests, seeps, marshes, and along streambanks