Though Small Spot Gardens is all about finding an ingenious use of even the tiniest patches of soil, not all of us have a garden-able plot in which to grow flowers or food. But solutions aren’t always so obvious, or sometimes they are just in such plain sight as to go wholly unnoticed. For example, if we have a house, then we have a wall, usually several of them. As this home demonstrates, the mantra of urban sustainability –think up, rather than out – can lead to an inventive and spectacular design. With all the sun from this south-facing wall, these multi-colored aeoniums and other succulents are destined to turn an otherwise bland beige wall into a vertical art form. Imagine!: According to the local nonprofit SPUR, San Francisco has over 120,000 buildings. There is a huge amount of potential here.