Pawpaw or Paw Paw (asimina triloba) is native to Eastern North America. It produces a remarkably delicious fruit. The coldest part of its native range is Northern Iowa and Southwestern Wisconsin. Paw Paw should be considered experiemental but worth a try in many areas of Zone 4, however areas with cool summer areas along the shores of the Great Lakes and dry summer, cool night areas of the West will not be ideal for its growth. The genetics available at Birch Grove Nursery were produced in South Eastern Iowa, Zone 5B.