If you garden in a dry area youll love this idea. Make your own olla. Whats an olla? An Olla is an ancient watering pot, that is buried in the ground in the area that you put your plants, when the plants need water the roots suck the water from the Olla.
nice DIY on making your own clay pot ollas BUT the challenge with clay pots (as opposed to plastic bottles) is that they won't hold up to freeze/thaw conditions plus they can be broken/cracked by plants' root systems
Global Buckets: Olla Irrigation describes a DIY method of using terra cotta pots to make a "olla" or slow irrigation container to add to your garden plants or other containers. The best part is that water is released to the plants on demand, as needed.