istorically, botanical gardens exchanged plants through the publication of seed lists (these were called Latin: Indices Seminae in the 18th century). This was a means of transferring both plants and information between botanical gardens. This system
Vertical Succulent Garden by floragrubb: 20 x 20" panels with 45 slanted cells to support planats and soil when mounted vertically. The unit in the picture is made of 6 panels, each $79. Now, if I could only figure out how to make the panels myself..