Bracken fern (Pteridium aquilinum, FACU) is another common native fern in Florida.  However, this fern usually occurs in uplands.  The fern's fiddleheads (immature tightly curled emerging fronds) are consumed, either cooked or pickled, in many cultures around the world. 

Caesarweed or Congo jute (Urena lobata, FAC) is a Cat. 1 FLEPPC invasive.  It has spread worldwide due to it's highly effective hitch-hiking bur seed.  The stalk is very fibrous and can be used to create extremely strong cordage.  As you may have guessed, it is in the same family as the Hibiscus (Malvaceae).