From the permaculture folks and article about Irrigation with Ollas
Thanks for finding this article, it really tells about how they work in our gardens. We use oya’s throughout our garden, 2 in the out side garden box to water 8 tomatoes, and up to 10 in the greenhouse for more tomatoes and peppers. They work very well in both locations, especially once the roots of the plants have reached the oya, which takes several weeks.
The only thing I would challenge in this article is how long the oya’s hold water - certainly not the 1 week to 10 days suggested for the 5 litre size. We use 6.5 litre size oya’s and on the hot days outside they might last 3 days. In the greenhouse, where the heat is usually higher, it would be 2 to 3 days. On cooler days yes, these times are extended. The biggest benefit for us is the even watering they provide to our plants.
We highly recommend them! You can find them here https://growoya.com/collections/shop-oya?gclid=Cj0KCQiA7bucBhCeARIsAIOwr-9gxSbAJK9JnY-cYqnJd_YiJlL2t3FCw7uT52RrIjjC5KNLCRc38EMaApAEEALw_wcB