The Pawpaw tree (or paw-paw, or paw paw) is an easy to grow fruit tree that is native to the eastern temperate climates of North America. The scientific name for the pawpaw is Asimina triloba. The pawpaw is the largest edible fruit native to America. Individual fruits weigh 5 to 16 ounces and are 3 to 6 inches in length. The larger sizes will appear plump, similar to the mango. The pawpaw fruit resembles a green mango, and the tree has many nicknames including “Hoosier banana”, “West Virginia banana”, and “wild banana”.
Pawpaw trees produce large, edible, green fruits, also called pawpaws. The fruit is fragrant and has a distinctly bright, tropical flavor, often described as taking a banana and a peach or mango and mashing them together. They are ripe when they seem ready to fall off the tree and pick easily. The flesh should have a slight “give”, similar to ripe pears. Eat them fresh or puree and make ice-creams, quick breads, or pies. They don’t store well and should be used as soon as possible, although refrigeration will extend their shelf life a bit.
Pawpaw trees have a rather deep and wide root system and once established don’t need much attention. That’s one of the great bonuses of them being native, they like it here. They don’t tend to be very tall (12-20′) and do well with a nice mix of sun and shade. In the wild, they often grow as an understory tree, in thickets. For the best results, pawpaw trees from different cultivars should be planted together. They are rather pest (see zebra swallowtail below) and disease resistant and do well is well draining soil. Pawpaws have gained popularity because of their nutritional value and because the leaves, bark, and twigs produce anti-cancer and insecticidal compounds called acetogenins. Deer do not typically feed on pawpaw trees, though raccoons and squirrels have been known to eat the pawpaw fruit.
Pawpaws requires a minimum of 400 hours of winter chill and at least 160 frost-free days. Pawpaws appear to be sensitive to low humidity, dry winds and cool maritime summers. The deep winter dormancy of the tree makes it highly frost tolerant, withstanding temperatures of -25° F or lower (hardy to USDA Climate Zone 5).
The leaf is dark green, and have an appearance of being a tropical fruit tree. The leaves turn yellow and begin to fall in mid-autumn and leaf out again in late spring after the tree has bloomed.
Pawpaw flowers have both male and female reproduction parts, but they are not self-pollinating. The flowers are also protogynaus, i.e., the female stigma matures and is no longer receptive when the male pollen is shed. In addition pawpaws are self-incompatible, requiring cross pollination from another unrelated pawpaw tree, however, bees show no interest in pawpaw flowers. The task of pollenization is left to unenthusiastic species of flies and beetles.
The Zebra Swallowtail, Eurytides marcellus, is the only species of the genus Eurytides (the kite swallowtails) that makes its home in the temperate zones of North America. The sole source of food for the Zebra Swallowtail’s caterpillars is the foliage, particularly the young leaves, of the pawpaw tree. If you see these beautiful butterflies flutter by, there’s a chance there might be some pawpaw trees nearby.