The pawpaw tree, Asimina triloba, is an American native from the central and eastern portions of this country introduced into British horticulture in 1736 by plantsman Peter Collinson. Collinson learned of the pawpaw through Quaker farmer-turned-naturalist John Bartram, who scoured the central and eastern states in search of unique and useful plants. Dubbed by Carl Linnaeus as "the greatest botanist of his time," Bartram freely sent his collections (including the pawpaw) back to his mother country, where Collinson introduced them to England.
Despite many ornamental and practical attributes, the pawpaw continues to remain a greatly overlooked and underused native.Asimina triloba belongs to a mainly tropical family (Annonaceae) of more than 2,000 species. Other members of this family include tropical delights such as soursop, sweetsop, cherimoya, and the custard apple. The common name, pawpaw, is actually derived from another tropical fruit, the papaya. As unrelated as the apple and the orange, the papaya and the pawpaw are similar only in their sweet taste and fruit shape. Among native trees, the pawpaw's fruit is one of the largest, approximately 3 to 6 inches long and usually weighing from 8 to 12 ounces.
Because it evolved with the challenging soil conditions and environmental stresses of the Chicagoland climate, the pawpaw is a relatively low-maintenance, pest- and disease-free plant. Pawpaws can tolerate a partially shaded site, but maximum fruit production will occur in a sunny location. Only light pruning and removal of dead branches is needed.
When selecting a pawpaw, remember that a larger specimen is more difficult to transplant due to the taproot these plants produce. A young container-grown tree between 5 and 6 feet tall is optimum for planting. The pawpaw requires infrequent but deep soakings to maintain the moderately moist, well-drained site it prefers. Both proper planting and follow-up care will aid in the development of a healthy, vigorous root system.
Certainly one of the most interesting features of the pawpaw is its fruit. The tasty, exotic, bananalike fruit is initially green and smooth-skinned, but as it ripens it turns yellow-brown and emits a sweet, perfumed aroma. When the fruit is fully ripe in September or October, the yellowish pulp surrounding numerous flat, brown, large seeds can be easily separated from the leathery skin.
The pawpaw is a relatively small, pyramidal tree with simple, weeping leaves and flowers with petals arranged in whorls of three. Versatile in the landscape, it can stand alone as a specimen planting, be grouped in mass plantings, or function as a screen.
Along with its exotic fruit, the unique leaves of the pawpaw provide several seasons of interest. In the summer, the large, drooping leaves recall the plant's tropical heritage. The crisp fall air stimulates the leaf color change to yellow and golden tones, which brighten any landscape. Subtle yet unusual flowers appear as the leaves open in spring. Maroon, cuplike flowers are usually evident through May, borne on pedicels, or stout stalks, arising from the previous season's woody growth.
Although the pawpaw can be self-fertile, best fruiting will occur if two or more cultivars are present. Some current cultivars that excel for fruit production include 'Sunflower'; 'Davis', with large, late-ripening fruit; 'Mitchell', which produces fruit with excellent flavor; 'Overleese', a late-ripening variety with fruit that can exceed one pound each; and 'Prolific' and 'Rebecca's Gold', both selected for good-quality fruit.
Planting a pawpaw can add more than just fine fruit or an enhanced view in your landscape. With it, you plant a touch of history as well.