Here's a hypertufa ball air pruning pot lol. The mix ratio is 2 parts perlite, 2 parts potting mix with peat, 1-1/2 parts portland cement, water to consistency which is like thick cottage cheese.
Using a tapered quart tub for a form, over it is a bread bag. Make balls of the mix and just go around, stacking as shown, making sure the balls touch so it will all stick together.
Getting the balls all exactly the same size is tricky by hand. Getting the moisture just right is even more tricky. Didn't press the balls into the side of the form, just laid them in next to each other. Wanted the same surface on the inside as you see on the outside. Think that will direct some roots out those little holes between every three balls?
When ready to up-pot, I plan to just set this pot inside a bigger one. This is a pretty weak design for a hypertufa pot and it will be very fragile compared to others but I believe it will hold together well enough to get to the next pot size.
They like cement eh I will give em some cement :)
P.S. Wife said it looks like dog poop haha