History

• Clay pots appeared on the scene around 6000 B.C. at the genesis of the Neolithic period. The invention of plastic occurred about 100 years ago. Plastic pots, mere infants in time, now rest on the shelves of retail establishments next to the familiar terracotta pot.
  
  

Clay

• The porous clay pot breathes, thereby letting air circulate throughout the roots of the plant. It also absorbs moisture, which gets rid of excess water in the soil --- an advantage for some plants. Along those same lines, soaking the clay pot in water can serve as a way to keep plants watered while on vacation.
  
  

Plastic

• Plastic pots prevent oxygen and water from entering the pot to nourish the roots of your plant. They also prevent excess water from escaping, which can cause root rot. In addition, plastic provides no insulation from extreme temperature changes.