Garden markers add personality to a garden and help you remember which row is tomatoes and which is peppers. Gather (or purchase) river rocks, some paint markers (pick up Sharpie brand at The Home Depot) and create these cute river rock plant markers.
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Insect hotel - Sustainable ideas including an explanation of the materials used, which insects they provide a habitat for and why you want that insect. This would be perfect to have as a project to build with a youth program