How should one properly discard a lulav, etrog and the hadassim bundle? Can they be thrown away in the normal trash or do they possess Kedusha?

The best way to discard of the Lulav and Etrog is to burn them with the Chametz before Pesach (Mishna Berura). If this is not possible, these are Tashmishei Mitzva, Holy articles used for a Mitzva and one should place them out in a field or somewhere were they will not come to desecration. They do not need to be put in Geniza. Rabbi Yitzchak Grinblat