interesting idea: plant box and belts . Hook together several belts to be large enough to go around if using real leather belts (from thrift store) . these "belts" look more like strap webbing and could be DIY made to size.
olive trees in courtyard. Evergreen, soft grey tones, hardy and easily shaped. My husband really wants one of these in our garden so he can have an "on-tap" supply of olives and a reminder of my Italian roots.