Hi all - i'm looking at building an overhead drip irrigation system for potted citrus, figs and more, mostly in pots around 20-30cm in diameter, but also 2x large half-wine barrels. Most pots are right next to each other, so some emitters / emitter arms might be about 1-1.5ft apart on the main line.
Cost is not an issue, it's a small garden and so my priority (apart from the functional irrigation) is something beautiful to look at and be around, and minimising of any plastics.
So i'm looking to build it entirely from 13mm copper pipes secured overhead (about 6.5-7ft ft off the ground) along one single line, with a t-join breaking out a perpendicular line right in the middle 3 metres long, to feed the 2x barrels and another couple of pots.
In total, there are currently around 20 pots that i'll be feeding with it.
Compression-fit for attachments between emitters and lengths of mainline pipe. All of the pots vary from 1 - 1.5 metres off the ground. From a birds-eye view, it would look like a giant "T" - 6 metres long along the fence, with one 3 metre arm coming out from the middle. The lines will be supported by some mounts on a fence and a couple of DIY pillars to carry the load at each end. Rachio or Bhyve tap timer at the front end.
I'm going to measure the pressure of the tap, but it's got a bit of kick and currently feeds a ground irrigation system with 30-40 drip punctures across a PVC line running about 50 metres.
I'm looking for advice on emitters and would love any insights. The main line from the tap will be about 6 metres long, and I want to avoid having 2x near-spaced drip emitters over each pot just to get better surface coverage in each pot, so I'm trying to find emitters that have arms with 3-4 drip holes fanning out from a centre point. I've seen brass spinning sprinkler type ones, but i think they'll cast the water too far. The emitters must be brass or copper.
My main questions:
1: Is a 13mm mainline copper pipe fit for purpose? Total run length may be around 10-11 metres, and ~20 pots for 25-30 emitters total.
2: In order to get the emitters a little closer to each pot, will attaching a 1-1.5 foot arm of copper directly down from the mainline closer towards the pot have any adverse effect on pressure that I should consider? This might add another ~5+ metres total to the run length, with the emitters at the end of each of these arms from the mainline.
3: Since the barrels will require more than the pots, are there any emitters that allow a much slower flow rate than others, or is pressure across an entire line of emitters uniform? My non-physics inclined brain tells me that even if the general pressure along a line is the same inside it, that this must be possible if some emitters have smaller/less outlet holes. Or is this best solved by having a section of pipe over the barrel that has 2-3 separate emitters extruding from it and line pressure equitably split between them thus solving this by simply having more individual of the same emitters?
4: Do bunnings have any sort of brass/copper emitter that might give me a wider array of drip holes to more thoroughly cover the surface of each pot?
Thanks for reading this onslaught 🙂