The main downside is it's currently manual and water is limited in the barrel. The rain barrel can only hold so much water and at times, I find my ZWave switch will turn off, then back on, which eventually drains the barrel if I'm away. I usually turn it on/off on hot nights when I'm home so I can monitor it.
Next summer I'll take a different approach with some of the ideas from this article. Perhaps use the rain barrel only if it's full (using sonar sensors that ping off the water level), but use the main house line as the primary.
That hacker/tinkerer in me wants to ultimately build a system that waters based on weather patterns/demands. I'll save that for next year.
Just last weekend I visited a 30 acre University farm - where they teach agroecology and have graduates worldwide who are running farms. I noticed that they were just using normal water spigots at different locations on the farm, and they had timers of different sorts on those spigots to what looked like 1" poly tubing. When I asked about how they adjusted for all their different crops, they said they just adjusted the timer for a set of rows and used a sharp point to poke different sized holes in the tubing at the base of plants. No big deal. They said it sometimes takes a few adjustments, but it works fine. The have been doing this successfully for decades. Very easy and very low cost.
Also an anti-siphon valve only works if it's above the water lines. If you store a hose above the spigot like many people do, you've just defeated the valve.
Use valves that are suitable for low flow/pressure and work off 24 VAC so you can use them with a cheap line-powered electronic timer.
If you need to filter or pressure regulate before the valves (probably at least filtering), be sure to use parts rated for continuous pressure at above typical household pressure. (100 psi ratings are probably enough)
Minimize the types of different tubing and emitters you use, it's easier to have spares that way, so if you weed with sharp implements and cut something it's not too annoying.
Don't go significant distances with less than the 1/2" black polyethylene tubing.
Drip-tape is super-cheap but mostly for farm-scale row crops.
The emitters I've had the best experiences with are the Netafim Woodpecker emitters and the take-apart-to-clean-out "flag" drippers sold by dripworks.com
I'm working with about 10 metres of head - a decent standing pressure, despite coming through 400 metres of 50mm polypipe - but it's too much for the specialised 'water barrel' type valves mentioned here. Combined with no power (if i had power I'd have a pump :) means it's also not feasible to use always-closed solenoids, or have sufficient pressure to reliably get residential grade water computer valves to open / close.
Since it's a ball valve operated by a motor it works with zero pressure. It's a relatively small ball valve but should be enough for almost all applications. I have one of those controlling about 100 meters of drip tubing from a source that's not more than 2 meters high (less if the tank is empty) and it works fine. For better flow I'll be trying one of these ball valves:
It's much less convenient as they don't have an integrated controller. I'll be trying it with this controller:
and a 12V battery together in a waterproof casing of some sort. I've been looking for a plastic case similar to the water timer one that's a screw on with an o-ring but haven't found one yet.
The actuator though, that looks very relevant to my interests. I've just done a google spiral on CR02 (and similar) wiring, to control via an arduino, say. With 3s to close / open, and only 12V required, this seems quite feasible to have a cheap solar charged battery sitting and running a half dozen of these of a manifold. The benefits of a switching solenoid in terms of power consumption, with a simpler control mechanism?
The last link you posted seems to imply it will talk to a solenoid (NC or NO) only - would be very curious how that goes.
I have several dozen old water timers with the o-ring seal ... where the o-ring seal has failed, and the insides rusted out. I now cover them all in thick plastic bags, and keep them under pit covers / galv steel lean-tos. Probably explains why they tend to last more than one Australian summer, too.
The way CR02 wiring works is that you have a common ground and then you feed the 12V to one of two wires. The valve takes care of stopping the motor when fully open and fully closed so it should minimize power consumption. So my plan is take that normal NC/NO relay and feed the 12V to the common wire and wire NC and NO to each of the two valve wires. Since the programmable relay itself is also powered by 12V I get away with a single power source. My hope is a simple pack of low self-discharge 8xAA NiMH or similar will last a season. But a 12V lead battery and a solar panel could work as well.
Aliexpress has a very big selection of different kinds of actuated ball valves. If they actually work reliably it seems like a great solution as it's a normal valve operated by a motor. See this for example for a selection of voltages and the 5 wiring types:
That one I linked was picked quite carefully to be stainless steel and CR02 wiring which seems to be the easiest to operate with just a single relay. I've received the relay but not the valve yet so I haven't tested everything yet.
>I have several dozen old water timers with the o-ring seal ... where the o-ring seal has failed, and the insides rusted out. I now cover them all in thick plastic bags, and keep them under pit covers / galv steel lean-tos. Probably explains why they tend to last more than one Australian summer, too.
Those are some rough conditions if the o-ring failing is enough to rust everything. I'd expect the threading itself to provide quite a bit of protection already. Can't imagine how you'd get much moisture through all those threads. One thing I have noticed is that you shouldn't torque the lid hard so as to not deform the o-ring too much.
and a DIN 12V power source like this:
all enclosed in an outdoor distribution box like this:
That way everything gets properly packaged using DIN elements. If you have a 12V panel/battery you don't need the AC->12V power source of course.
Or would the possibility of the system not running be a disqualifier?
There are switching solenoids that only draw power as you change state. Downside, they don't fail safe. They're also more expensive, and AFAICT you can't use standard (NC / NO) controllers with them. To complicate matters, switching solenoids usually want a certain amount of pressure (about twice what I'm working with).
It's an area that's slowly getting better served by cheap fab places out of China. You can already get A$20 'residential' grade 13mm single line water controllers that are mostly reliable, but their valve comes down to about a 1mm hole, so big impact on flow rate, and highly susceptible to debris.
what are you using instead?
I wonder why it isnt popular in US, price too high?
Best advise I saw in the tutorial was to make sure tubing and fitting sizes match. It will take a few days, but they will blow apart when you aren't looking.
Such a satisfying description
I container garden in pots and have to over water to ensure everything gets enough, but this causes all sorts of other problems of pooling water and leaked water onto the balcony, leaching of nutrients.
There are different emitters for different rates ... I have 1gph as well as .5gph emitters for various purposes and I think there are other choices as well.
I would think you could run the water the same duration for all of them, but vary their irrigation with different rate emitters.
I recommend graduating from the hardware store tooling to the professional Netafim hoses/emitters/couplings.
The 'water well' pots may be a simpler, cheaper, reliable option -- if you can hook up multiple inverted water bottles, or some ballcock arrangement into a cistern and share out from there with 13mm pipe -- if the bottoms of all your pots are the same elevation.
There's a small period of time while the roots head down to find water, that you need to top-water, but, again, convenience .vs. cost .vs. resilience tradeoff.
Is anybody qualified enough on this topic here to counter me on this?
Am I overcomplicating things? Or is it really that hard to get it set up properly with correct pressure such that I'd be better off just hiring someone to install it?
Some good info here:
Or am I overthinking that part of it?
The pressure-compensating drippers, as mentioned in TFA, may be useful for you, depending on your run lengths, and contours. Bit more expensive, but the sound of lots of emitters going 'click' at the same time can be quite cool.
For most systems I use a dribbler, rather than a dripper, device. I use 25mm (well, 1") LDPE almost everywhere so I can easily puncture and insert an adjustable barbed dribbler. Do not go for the cheap ones - they won't last one summer. Dribblers let you compensate for distance from the tap and contour changes.
You should have a go designing and implementing something - it can actually be a whole lot of fun.
The one area where I feel like irrigation goes beyond my comfort zone (as someone who has only laid out irrigation like twice) is if you're working off of a well, since irrigation with a flow rate that matches the well poorly can cause the pump to cycle excessively and burn it out faster. But if you're on city water that's really a zero concern.
Have you looked in to whether a hydraulic accumulator would suit this purpose?