Garden wall wheel - a stone wall wouldn't look good with our current house but this is a neat idea! I bet this could be incorporated into the wooden fence I want, and the wheel painted an accent color like blue, white or silver :D
Succulent tree trunk - instructions are not in English but the idea is pretty basic. Tree trunk + removal of some wood + soil, water & succulents = awesomeness in your garden! You could even hang this from a patio at eye height.
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