It doesn’t really ‘self-water’...the box has a reservoir of water in the bottom that you keep filled...just run water from a hose down the fill tube until water starts running out from the overflow drain. The plants access all the water they need as they need it. Just make sure that it never runs dry (it would take a breathtaking level of neglect for that to happen). I have a number of these EB’s...they grow just about anything anywhere. Drought never a concern because YOU supply the water. No weeding.
I’m going to try putting 2 molasses pots together for my roses next to the garden shed. The bottom pot, I’ll put some inches of pea gravel and add fertilizer and water. The top I’ll put in a 1” pvc pipe over a drain hole, punch holes for the roots to feed through, cover the bottom with a screen to keep in the soil, plant the roses and other stuff then see what happens. Molasses pot earth grow?