|Viola sp., Nature created living wall, vertical green|
Bird droppings had provided a small amount of organic matter such as nitrogen and the like.
The crevice was exposed to moderate sunlight yet was shaded enough to keep the violets from becoming too dried out or desiccated.
Though usually considered an annual plant, native violets may do very well in vertical green applications, especially where shade is involved, even surpassing many other living wall plants in durability under some situations.
I always learn so much from nature. And importantly, most times nature teaches us about crucial design issues on an incremental basis. Learning what plant grows best how in what media from looking around as you experience everyday life is one of the best methods of understanding living wall and green roof design. One does not have to walk beneath the great constructed living walls of the world to learn about successful vertical green design (though it helps). Nature too, can teach us incrementally through her selection and use of plants we see appearing in the cracks of walls, on the tops of buildings, across bridges and even growing out of hot asphalt pavements.
You see, nature has first created all plants; from simple crevice growing violets to those in the beautiful man-assembled living walls.
Learning from the original teacher is the best way to learn.