Review on 12-Pack OZMI Plant Self-Watering Spikes With Slow Release Control Valve - Automatic Irrigation Equipment For Home And Vacation Plant Watering, Adjustable Drip System For Optimal Water Volume by Mason Gordon

I'm located in Oklahoma and during the hottest part of the year my potted plants sometimes need to be watered twice a day which I really don't have time to always do. So I give them a thorough watering early when it's coolest and then use the self watering spikes to slowly and continuous!y water throughout the rest of the day. Works very well. Did take me a while to figure out you need to open the valve completely first and then back off to get exactly the right rate of drip.