It would be interesting to do a comparison. Are they available online in the uk maybe? My only concern would be watering as they look really open compared to an airpot.
I expect all the smaller sizes would be. There’s a lot of identical knockoff brands for net pots. That really big one is a bit of an oddity, though. I haven’t been able to find that size online anywhere. Moreover, the hydroponics shop I got it from said they were discontinued. Maybe there just isn’t a market for absolutely massive plastic pots with lots of holes in them, lol.
They are definitely as open as open gets. I might have to wrap a mesh around the big one to keep the soil in it even. They basically just provide structure to keep the soil and root ball stable.
One unexpected side effect is that you have to weed the sides of the pot as well because weeds will happily grow out the sides.
It would be fairly easy to make a mesh pot that is the same size as the air pot by rolling into a cylinder and inserting a round bottom piece that is up off the ground/bench like the bottom of the air pots I have seen. Use of 1/8" (3 mm) mesh would be my choice and a minimum of 3 of each pot using nominally identical seedlings. I can make the mesh pots if someone sends me the air pots.
It would cost me too much to send them to the States. I think I could make the mesh pots though and I have oodles of airpots. I reckon Japanese larch would be a good specimen to use. I have loads of them in airpots at the moment all grown from seed. What do you reckon? I have tried a deshojo cutting (once the roots were well established) and its trunk thickened quite rapidly.
My comment about sending them was a bit tongue-in-cheek. I look forward to your results. I would do at least 3 in each type of pot and do my best to have matched pairs with careful recording of data. Of course more pairs would be better. I would also place them on a square or rectangular grid so that they alternate positions.
I have been using airpots a lot, in part because i got a great deal on a huge case of used ones. One thing i love about then is that its quite easy to connect two together and make larger or oval pots and simply cut bases out of other things (i sometimes simply set bottomless pots into Anderson flats and use that as the bottom)
i also have used the adjustable bottom as a root reducing method. Allowing me to carefully open a container, shave off an inch from the bottom of the rootball and move the bottom up a row and close the container back up. Stepping it up one row at a time till its wonderfully shallow and filled to the brim with fin roots continuously egged on by the air pruning.
You can also use the airpot to ready a tree for the first bonsai pot by moving the bottom up to halfway or higher and potting into it to get a really compact root system. Works especially well in a 1 ltr airpot for shohin material
I might try air layering mine a few years down the road to establish the nebari. I suspect dawn redwood air layers pretty well, both as a deciduous and as a cypress family. That way I can keep powering up the trunk without worrying about the roots for now.
I did the first cutback end wiring on it, and my goodness was it tough; the trunk has already really hardened. Probably because it happened so fast. I kind of wish I’d wired sooner, but I think it will work well as a more subtle movement