- Hardiness: USDA Zone 4/USDA Zone 5
- Size at Maturity: 15-30 feet tall and wide
- Edible, Flowering
- Requires Pollinator
- Sources: Seeds from New Jersey, Vermont, and Ontario
Asimina triloba, Pawpaw
The Pawpaw (Asimina triloba) is the largest fruit native to North America and has a range that spans from northern Florida to southern Ontario. Pawpaws are small deciduous trees growing 15 to 30 feet tall and wide with large tropical-looking leaves. Pawpaw is a temperate climate member of typically tropical Annonaceae family that includes soursop and custard apples.
In the wild, Pawpaw grows as an understory tree along rivers and creeks and forms colonies by root propagation. As a result, it prefers moist soils and shade as a seedling, though, mature trees in full sunlight are more productive.
Pawpaw trees produce burgundy flowers with male and female parts, but the trees aren’t self-fertile (except for some cultivars such as ‘Sunflower’), and require a partner to fruit. Carrion beetles and flies pollinate their yeast scented flowers. Pawpaw fruit is variable in size (2 to 6 inches) and oval or kidney-shaped. The flesh is creamy with a flavour described as a combination of mango, banana, and citrus.
Attempts to bring fruit to the market are ongoing and made difficult by its soft-flesh and short shelf-life. Advances in breeding and processing are making it more common – typically as a pulp or flavour in ice cream and beer.
Growing Pawpaw Trees in Edmonton
Depending on who you talk to, pawpaws are USDA zone 4 or 5. I have never seen pawpaw growing in Edmonton, but there haven’t been many attempts. To increase the chances of success, I have been selecting seed sources from the pawpaw’s most northern range. I have started seedlings from New Jersey, Vermont (Zone 4), and Ontario.
Growing pawpaws in Edmonton is a passion project for me. Likely, most seedlings won’t be suitable for our climate or produce ripe fruit in our shorter season. However, if a few individual plants perform well, they can be used as stock for the next generation of pawpaw trials. Let me know if you’d like to join me on this journey.
For more information on the natural, horticultural, and cultural history of Asimina triloba, I highly recommend Andrew Moore’s ‘Pawpaws: In Search of America’s Forgotten Fruit.’