Hydroponic Hex Wall

I was approached by a local farmer/educator who was interested in doing 3d printing to expand hydroponics, and he had learned that I had done one of the hydroponic towers ( https://www.thingiverse.com/thing:3405964 - unfortunately this link is dead and I do not know where it has gone ), but we had a problem with the scalability of those towers.

So he asked me to come up with a scalable solution. The requirements?

1) We had to be able to (eventually) fill a 1m x 1m wall.
2) I had to take less than 6 hours to print a single part
3) The system had to maintain a 150mm distance between each plant
4) The overall system had to be simple enough for a 3rd grade class to assemble.

Hence the hex. The hex tile is 150 mm from flat-side to flat side, making it always 150mm from the centers of the hex. Each hex requires 2 M4 bolts with t-nuts to hold it on the frame, and the frame can be constructed out of 20mm v-slot.

The tile takes 5.5 hours to print on my Creality 10S-Pro prin