Instead of using plastic or clay pots as planters, why dont you try using tree logs?
They look so beautiful and whimsical!
Leave only about an inch thick or more around the sides.

Image credit: Some Room to Grow via YouTube
The key to this method is to keep the coals constantly hot.
*All these images are credited toSome Room to Growvia YouTube.
How To Make A Log Planter For Your Garden

