False Nettle
Boehmeria cylindrica
2 to 3 feet tall and wide
Fast rate of growth
Light to moderate shade
Low salt and drought tolerance
Prefers wet, to moist well drained soil with humusy top layer
Zones 9 to 11
Short lived, annual, as tall as wide, with greenish flowers from summer to fall.
Larval host and nectar plant for red admiral (Vanessa atalanta) butterflies.
http://florida.plantatlas.usf.edu/Plant.aspx?id=712
http://regionalconservation.org/beta/nfyn/plantdetail.asp?tx=Boehcyli

