Used plastic flower pots, especially black ones that came from the nursery, often become nothing more than dust-gatherers and space-hogs in the corner of your garage or storage shed. Although storing the pots is better than sending them to a landfill, where it will take an indeterminate amount of time for them to degrade, you can also recycle these plastic containers at a facility that accepts such items, or you can implement creative ways to use the pots once again.
How to Recycle Plastic Flower Pots | eHow.com