Hundreds of years ago, Spanish settlers in the dry regions of the Americas developed a unique method for irrigating plants: burying terracotta pots next to their plants, which they would fill with water. Since unglazed ceramics like terracotta are porous, allowing water to slowly pass through their walls, the plants next to these buried pots would receive a steady flow of water.
Called ollas, this technology was used for hundreds of years up until the introduction of modern irrigation technology. And though some horticulturalists are trying to reintroduce the olla to modern gardens, it's an idea that few know.
The olla is integrated in the center, with the surrounding pot filled with soil and plants:
The water only moves out from the center when the soil around it becomes dry, which happens as the plant place in the outer section draw the water in the soil into their roots. The result is extremely efficient watering, with the plant getting just as much water as it needs when it needs it.
It occurred to us though that Joey Roth's planter design could easily be converted into a zeer pot, where one could fill the outer portion of the container with sand and water, which would then cool the inner container through the effect of evaporative cooling.
That's something that would come in really handy during the summer when entertaining outdoors. And to give credit where it's due, Joey Roth's design is a lot more stylish than the flower pot-in-flower pot contraption most greenies might put together!