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Pawpaws—Tropical Trees for the Temperate Zone
Plants & Gardens News Volume 12, Number 3 | Fall 1997
by Barry Glick
Consider an easy-to-grow, hardy-to-zone-five (at least), ornamental tree with a tropical appearance, large interesting flowers, delicious fruit that tastes like a cross between bananas and vanilla custard, aaaaand a vitamin content that rivals that of citrus—all wrapped up in one package. That's a plant with a lot of punch.
Small wonder that the pawpaw, Asimina triloba, is rapidly gaining a place in today's garden and backyard orchard.
My first encounter with this wonderful plant was in the Chadds Ford, Pennsylvania garden of Dr. Darrell Apps, an extraordinary plantsman who is world renowned for his fantastic Hemerocallis (daylily) introductions. At the time, Darrell had limited garden space, so his grant of turf to a particular tree was my first clue that the pawpaw was something special.
I visited the garden on a crisp, clear autumn day and noticed a shapely tree with outstanding seasonal color. We strolled over to get a closer view and I glanced up to see banana-like clusters of fruit hanging pendulously from the branches. The pawpaws were just ripening, so Darrell, being his generous self, got a five-gallon bucket and vigorously shook the tree, pelting me with fist-sized fruits weighing over a half-pound each. It was worth the beating—we sat down under the tree, peeled back the skins, and feasted on one of the most unusual tastes and textures I have ever experienced. I was hooked.
When I got home, I immediately pulled out all my North American Fruit Explorers journals to learn more about the pawpaw, which is a member of the Annonaceae family—sibling to the soursop, custard apple, and cherimoya. The more I read, the more I wondered why this, the largest native fruit in North America, wasn't more popular with the home gardener and the fruit-consuming public.
A Little History
Over the centuries, pawpaws have had their moments in the sun. One of the first recorded historical references to pawpaws dates back to a De Soto expedition in 1540. The Spanish explorer wrote of Native Americans cultivating the pawpaw and introducing it to the Europeans. The pawpaw was apparently a big hit with the newcomers. In 1736 botanist John Bartram sent some pawpaw specimens back to England, but there's little evidence that the Brits at home were as keen as their countryman abroad about the New World taste sensation.
During the 1800s, U.S. interest in pawpaws went into a bit of a slump, rebounding after the turn of the century—in 1917 the American Genetics Association sponsored a "best pawpaws" competition, attracting a respectable number of entries. Pawpaw popularity reached a peak during the Great Depression—people delighted in the fall harvest of the cheap, accessible pawpaw to brighten otherwise dreary diets. Interest in pawpaws took another dive in the years following World War II. During that economic boom period imported, more exotic fruit became increasingly easy to obtain.
In 1988, the pawpaw made another comeback. That year, USDA agricultural economist Neal Peterson—who is justly referred to as the foremost pawpaw expert in the Universe—founded the Pawpaw Foundation (PPF), launching a one-man crusade to enlighten the masses about the virtues of this forgotten fruit.
A West Virginia native, Peterson tasted his first wild pawpaw on a graduate school research expedition to the Monongahela River flood plain. He was smitten by the sophistication of the fruit. As a genetics student, he was familiar with the history of domesticated crops and knew how radically fruits and vegetables have been improved by human intervention over the centuries. "You wouldn't recognize the ancestor of corn," he explains. "It was very hard and had maybe six or eight kernels on a whole ear. I started thinking about the potential of the pawpaw, the incredible raw material we were starting out with!"
Peterson spread the word. Today PPF boasts over 300 members, both across the United States and abroad. Among its many activities, the organization oversees two orchards totaling over 1,200 trees at the University of Maryland. It also lends fruit for research and taste-testing to scientists, horticulturists, and geneticists studying pawpaws, along with technical assistance. Recreational gardeners aren't neglected, either; PPF gives advice to anyone who wants to grow the tree in their backyard. Members receive a very informative newsletter free of charge, and annual dues are only $20—a bargain in my book.
Another mecca of pawpaw research is Kentucky State University (KSU), which recently received authorization to become a USDA germplasm satellite repository for all species of pawpaws.
Scientific studies have targeted two areas: research is currently underway to isolate compounds from pawpaw twigs that have been shown to have promise in cancer therapy. The compounds are also being tested as organic pesticides. So far one extract has proved effective at killing pests such as nematodes, tobacco horn worms, bean beetles, potato bugs, and cabbage loopers.
Planting, Care, and Propagation
Whether pawpaws prove to be a major player in the medical or agribusiness arena remains to be seen. What is certain, however, is that happy, healthy pawpaws produce bushels of delicious fruit. And pawpaw trees are not at all as difficult to grow as their reputation holds, though they can be finicky to establish.
The natural range for pawpaws extends from southern Ontario to the Gulf Coast and west to Nebraska and Texas. Pawpaws require shade at the germination stage—full sun will kill seedlings. It's a good idea to plant below a bush or to create artificial shade. By the time they've grown into saplings, pawpaws are sun hardy.
Pawpaws prefer a slightly acidic soil (pH 5.5-7.0), well drained and fertile. If your site is in full sun, you can expect the tree to take on a narrowly pyramidal shape with dense foliage that droops down to the ground. Grown in the shade, the pawpaw will likely sport an open-branching silhouette with few lower limbs and horizontally angled leaves. Pawpaws are typically small trees, ranging from 12 to 25 feet in height. Several trees should be planted since most are self-infertile.
Pawpaws bear fruit in autumn. The fruit is wonderful eaten fresh off the tree, but it can also be harvested before it ripens and stored in the fridge for a couple of weeks. Pawpaws are relatively perishable, however, so if you have more than you need, treat your friends and neighbors to a new taste experience.
Pawpaws in Person
At Brooklyn Botanic Garden, you can see mature pawpaws on the left near the bridge spanning the brook as you walk west from the Visitor Center. A younger tree makes its home in the Native Flora Garden, a two-acre collection of plants that grow within a 100-mile radius of New York City.
Additional information about pawpaws is available from Snake Jones (contact for PPF), 137 Atwood Research Facility, Kentucky State University, Frankfort, Kentucky 40601; 502-227-5834; e-mail: snake@uky.campus.mci.net
Nursery Sources:
432 Burnt Ridge Rd.
Onalaska, WA 98570 Miller Nurseries
27635 S. Oglesby Rd.
Canby, OR 97013 Campberry Farms
RR 1
Niagara-on-the-Lake
Ontario, Canada LOS1J0 Northwoods Retail Nursery
27635 S. Oglesby Rd.
Canby, OR 97013
1385 Campbell Blvd.
Amherst, NY 14228 Pampered Plant Nursery
PO Box 3
Bourbannais, IL 60914 Hidden Springs Nursery
170 Hidden Springs Lane
Cookeville, TN 38501
hiddenspringsnursery@hotmail.com Sherwood Greenhouses
PO Box 6
Sibley, LA 71703
Barry Glick is a freelance writer and the owner of Sunshine Farm & Gardens, a nursery that carries pawpaws in Renick, West Virginia.