I’ve grown Pawpaw (Asimina triloba) since about 2019. A few named varieties, but mostly from seed. One tree (‘Sunflower’) started flowering this year.
My goal is to be able to grow pawpaw in the first place. The tree is limited by hardiness in my climate. I colleague grows them in Gothenburg, much more north of here, so I know it is possible. I want to grow them outside the greenhouse as a proper tree.
With pawpaw, a rule of thumb applies: The bigger the seed, the bigger the fruit
The last 2-3 years I’ve grown hundreds from seed every year. I usually stratify the seed and then let them germinate warm inside. The plant seems to like much more heat than our usual climate provides. Germination is hypogeal, ie. takes place below ground. I put all the seed in one container and when I see signs of germination, I take them outside to give the roots more space.
Sometimes I do that a bit too late, like here:
I grow them on in large trays I dumpster dive from the recycling station:
Or in deep pots. The juvenile taproot on pawpaw is really long. Some people obsess about having deep pots. It doesn’t matter that much, because you can prune the taproot and eventually it will spread out anyway.
I love working with pawpaw seedlings. The roots smell like Magnolia. The Cherimoya-family of which it is the only temperate species I know of is in the Magnolia order. I find those connections fascinating. You can smell taxonomy.
Tall containers take up less space though. These are some of the seedlings from this year
At the end of the season we grade all the seedlings. With pawpaw, I’ve heard that they typically start flowering when they reach a certain height. Therefore, I go for maximum growth as the first selection criteria.
The first two years they usually die in the winter if not protected. I keep them in a heated greenhouse.
