Complex sentence: Hans Christian Andersen, who was a frequent visitor in Hornemann's home in Copenhagen, used him as model for "the Professor of Botany", who understands the gestures of the flowers, in the tale "Little Ida's Flowers".
Split into simpler sentences: Hans Christian Andersen was a frequent visitor in Hornemann's home in Copenhagen. Andersen used him as model for "the Professor of Botany", who understands the gestures of the flowers, in the tale "Little Ida's Flowers".