Pawpaw Habitat & Climate
This is where Pawpaws will grow.
They are adapted to a wide area!

In the map above, the native range of the Pawpaw tree is shown in PURPLE,
and the area in which temperatures are suitable for its growth are in GREEN.
The boundaries are intentionally imprecise, because of local microclimatic variability.
In the GREEN areas, Pawpaw trees can grow, but may not bear fruit if conditions are otherwise sub optimal. See Climate, below.

Pawpaws are native to the region in the South Eastern USA, shown as the second green color on this map.
Given enough water and a suitable temperature range, however, Pawpaws will grow in many other parts of the world.

Habitat
The Pawpaw, Asimina triloba, is the largest edible wild fruit native to the USA, occurring naturally in moist, shady places in most of the eastern half of the USA, from the Gulf Coastal plain to the Great Lakes, and from lower New England, to the edge of the southwestern plains. They are seldom found near the Atlantic or Gulf coasts. The Pawpaw's preferred habitat is rich, moist bottomland, but will also grow on other sites that are well~drained and sunny or partly shaded. Within their native range, they can be found almost anywhere from river bottoms to hill tops. The soil should be slightly acid (pH 5.5~7), deep, fertile, and well~drained. Good drainage is essential to success. Pawpaws will not thrive in heavy soil or waterlogged soil.
Pawpaw trees will grow in USDA zones 5A through 9.
(Please refer to the USDA Plant Hardiness Zone Map.)

Climate
Pawpaw trees do well in humid continental climates, similar to their native range. They require warm to hot summers, with at least 160 frost~free days; mild to cold winters, with a minimum of 400 hours of winter chill. Although the trees will grow with less winter chill, they may not fruit. And a minimum of 32 inches (81 cm) of rainfall mainly in spring and summer.
Pawpaw trees do not like low humidity, dry winds and cool maritime summers.
They can withstand temperatures of -25° F (-32°C), while dormant.