Ollas (or Oyas) is a traditional, natural way to save water, save time and grow better plants. Bury into the soil, fill with water and watch your plants thrive! It's a porous terracotta pot you bury in your planter and you fill with water. Moisture will seeps out slowly through the walls to water your plants right at the roots. Over time the roots attach themselves to the outside of the Olla and draw water out as they need it. Your plant will take just what she needs—no more, no less. Easy !