Maryland Grows

One of our most frequently asked questions in the developing orchard at the Baltimore County Master Gardeners’ Demonstration Garden may surprise you (it did us!) — “What do you know about pawpaws?” *

The pawpaw (Asimina triloba) is a small native fruiting tree found along stream banks and forest edges and often as an understory tree in moist areas. My first encounter with them was along the canal towpath in Potomac where I found 6” soft yellow fruits littered the ground. There was a short step from that discovery to growing my own.

Pawpaws produce the largest edible fruit native to the USA, with a range south to LA and GA, north to IL and PA, east to the coast, and west to Nebraska. An attractive tree with large drooping leaves, pawpaws have a pyramidal shape and generally reach 10-20’ in height (but can be controlled for size). Although in the wild they seek some shade they should be grown in full sun for best fruit production. Trees tend to sucker and form clonal colonies in shade but this can be easily controlled. Growing two or more varieties will produce a greater fruit yield. They are a temperate member of a tropical family that will grow and fruit in Zones 5-9. Ideally, pawpaw trees like a soil pH between 6 and 6.5 but will tolerate a much broader range. Consistent moisture is key as well as good drainage. Once established they are quite drought tolerant. Best of all, pawpaws require no herbicides or pesticides to thrive, having few pests or diseases.

In spring small maroon bell-shaped flowers emerge before leaves. These flowers have a mildly yeasty smell to better attract their pollinators: carrion flies, fungus gnats, beetles, and ants. The flowers have both male and female parts. The female pistils and male stamens mature at different times within the same flower, so a single flower is capable of self-pollinating. This, however, rarely allows for fruit set and two genetically different trees are necessary for solid fruit production.

Fruits form in small clusters rather like bananas and slowly mature through the summer. In Maryland, they will ripen by mid-September. When ripe, the fruit will drop to the ground (warning: many four-legged critters enjoy pawpaws once they hit the ground!). Resist the temptation to pick green fruit – if picked too early it will not ripen. The fruit is usually 2-6” in length often with a shape that resembles a small slightly irregular mango. In the wild they are usually 1/2 lb. or less but cultivated varieties can exceed 1 1/2 lbs.

Experiment a little with the fruit to see whether you prefer them just off the tree or allowed to ripen a few days (the skin will turn black) for added sweetness. The texture is creamy or like custard and the taste is often described as a cross between a banana and a mango with hints of pineapple. The skin is thin and easily removed. Try cutting one in half and scooping the pulp out with a spoon. Pawpaws have two rows of large, glossy, black seeds. Many cultivars have fewer seeds and a higher pulp to seed ratio. The fruits are highly perishable, a trait that contributes to the challenge of commercial value. 

In my yard trees seed freely. Seeds must be kept moist to germinate and do require stratification. They are tap-rooted so it is preferable to transplant them when very young. If purchasing plants, potted are preferable to bare-root as the root is fleshy and brittle and requires good care when handling. Pots should also be at least 7-9” deep to accommodate the long root. From seed to fruit is approximately 8 years.

Importantly, pawpaws are the only larval host for the beautiful zebra swallowtail (a large black and white striped butterfly). The caterpillars produce no significant damage but if you see holes in your leaves, it was most likely due to this caterpillar. Lucky you!

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Pawpaws were a significant food source for Native Americans, high in potassium like bananas, with significant amounts of vitamins A and C, and high in unsaturated fats. They were collected from the wild by the early colonists. In the early 20th century cultivars began to be developed in earnest. After centuries of native crops, availability in the wild has greatly diminished and pawpaws are now more of a local specialty. Some of the best new cultivars are Peterson Pawpaws named after Eastern rivers such as Potomac, Allegheny, Rappahannock, and Shenandoah. For curated lists of cultivars see the references below. Young trees are readily available at many nurseries.

So what to do with your abundance of fruit? Anything you can make with a banana can be substituted with pawpaws. Pawpaw bread is delicious. So is pawpaw ice cream, recipe below (great with walnuts added).**
     2 cups pawpaw pulp or more
     1 cup sugar
     2 cups cream
     2 cups milk
Combine the pawpaw and sugar. Stir in the cream and milk. Pour the mixture into an ice cream maker and freeze according to the manufacturer’s directions.
(Recipe from Pawpaw: In Search of America’s Forgotten Fruit)

Resources:
PawPaw: In Search of America’s Forgotten Fruit, Andrew Moore, Chelsea Green Publishing, VT, 2015.
For the Love of Pawpaws: A Mini Manual for Growing and Caring for PawPaws – From Seed to Table, Michael Judd, author and publisher, 2019.
North American Pawpaw Growers Association, www.ohiopawpaw.com
Kentucky State University Pawpaw Program, www.pawpaw.kysu.edu

* We have two young pawpaws in the Baltimore County Demonstration Garden that blossomed just this year but did not produce fruit. Fingers crossed for next year!

** [Revised 8/3/21: Fully ripe pawpaws can be enjoyed in small amounts as a seasonal treat. Long-term consumption is not recommended.]

By Deana Karras, University of Maryland Extension Master Gardener, Baltimore County. To connect with Master Gardeners in your county, visit the Maryland Master Gardener Local Programs page.