This is great info. I've wanted to grow some for years, but I live in CO, and won't be moving to a region where these are viable for a few years yet, so I've got plenty of time to plan. I had no idea there even were cultivars for this fruit, but I was aware they like to start in shade, then explode once started.

In the Southwest, there are many environments where a tall, shady plant grows quickly, sets the stage for plants that need only initial shade, and then the fast-grower eventually loses out on the plot once the slower-growers have a chance to establish themselves. Once those slow growers are in place, a new generation of smaller, shade-loving plants will often follow, filling in the area that the fast-growers left.

I wonder if there are analogues you're meant to plant first, to get the pawpaw going.