That’s a really cool thought – a living neon that actually glows from biology instead of circuitry. I love the idea of bioluminescent plants on a façade, but I’d have to worry about a few things. First, they need a reliable light source to trigger the glow, so you’d still need some artificial lighting unless you’re using a plant that works in low light. Second, the moisture, nutrient and temperature control on a concrete wall is a nightmare; I’ve spent a year fine‑tuning a tiny greenhouse to get the right humidity for my seedlings, and scaling that to a building would be a whole new level of precision. And honestly, would they ever be bright enough to replace the glare of neon? Maybe a hybrid with a low‑power LED backup would be more practical. Still, the idea of a skyline that looks like a living aurora is worth exploring – just don’t forget the soil schedule!