So in my urban garden, I've wanted to make better use of my rain barrels for watering...but I'm also a lazy gardener. And one who likes to leave my garden to its own devices for weeks at a time to go camping or see family. What I wanted, was a way for my rain barrels to
water my plants automatically. Last year I tried making capsule-type ollas (glued 2 terracotta pots to each other) and plumbed them with drip irrigation lines to a barrel. Without pressure behind them, the capsules worked "ok." Once filled, the pressure from the barrel would cause them to leak badly and they would drain the 85-gallon barrel quickly. This year I reworked the original idea and used larger flower pots, metal "lids," and a micro float valve for each pot. Once the float is lifted, the barrel pressure is removed from the terracotta pot, and only the water inside the pot applies pressure. My micro tomato & pepper garden is a month and a half late going in this year, but I think I've finally gotten the watering system automated with no electricity and no oversight. Hopefully I'll get a few more plants in the space but I struggled just getting these in this year so if this is all I grow in this bed so be it
Attached are pics of the garden plot, olla/pots, and float valves. The brick visible in 1 pic is holding a temp blocking plate since I have 1 more lid and float valve combo to make so it is just to keep debris out of the flower pot underneath.