Jug irrigation - designing 10L jugs to drip for 1 week
I have found the GardenWeb community to be extremely resourceful and would like your help. I have searched the Web for expertise on designing drip irrigation from jugs and found nothing, surprisingly. It's proving to be more difficult than one would think to get a 10L jug to drip for one week.
We have a very long dry season here - 8 months. Young and even mid-aged trees die. Discarded 10L drinking water jugs are plentiful.
I want to bury the jugs, lid up, next to trees (labor is cheap here). Plastic will then last for years if out of the sun. Lid up makes it easy to fill them. I drill holes in the bottom of the jugs. I keep the cap on tight, creating a vacuum inside.
The problem is that with the lid loosened the jugs empty out too fast (when even a tiny pin hole is made), and with the lid tightened, even a 2mm diameter hole doesn't leak enough. When I put a tiny pin hole up at the top where air can enter, the water floods out.
Is there any technology out there for converting jugs to drip irrigation? This would involve gluing a valve into the bottom of the jug. The valve would be designed to drip a certain amount per day, with the cap either loosened or tight.