In Florida Simpson gained the nickname "The Sage of Biscayne Bay" and wrote several books about tropical plant life around Miami. His backyard contained a tropical hardwood hammock, which he estimated he showed to approximately 50,000 people. Though he tended to avoid controversy regarding development, in Ornamental Gardening in Florida, he wrote, "Mankind everywhere has an insane desire to waste and destroy the good and beautiful things this nature has lavished upon him". In 1927 he received an honorary doctorate from the University of Miami. Simpson Park Hammock near Downtown Miami is named in his honor.