Structure + focus = hot
Spreading cacti across a rack with strong geometric shapes create a focal point in the room. The grey-green shades of cacti can take on any strong-coloured background and the open structure they're placed in creates a visual space around each of the plants so that they appear a little different and a bit more contemporary.
Geometric talents
Cacti suite geometric shapes so well because they too are an example of geometry. There has even been research done on this: the Cactus Primer from Harvard University. What’s amusing is that the mathematicians are unable to explain why cacti prefer to grow so geometrically, but biologists can. The ridges and spirals make the plant sturdier and allow the wind to swirl around the plant in the wild so that it cools down better. Nature wins!