Ceramic pots (ollas) are permeable clay pots that slowly release water underground, reducing evaporation. They are a useful way to irrigate established plants, but they should not be relied upon to water seeds. 

Watch this short video about the olla’s we use in our demonstration beds at ZIlker Botanical Garden.

Ollas generally cost between $25 and $40, depending on their size. You can purchase Dripping Springs Ollas locally at several garden stores. 
​
If this is beyond your price range, you can substitute them with glass or plastic bottles. Simply poke or drill small holes in the bottom of the bottles and bury them in the ground.