I like gardening. Digging up the ground, planting seeds and seedlings, watching shrubs grow, harvesting fruit and vegetables, eating a meal composed all or partly of home-grown ingredients, are all very satisfying activities. But there is hard work too, and one thing that can undermine the success of the garden is lack of water, or irregular water. Something I have always wanted to do and have now had some measure of success with, is automatic watering of the garden. I’m a technically minded person so I get a lot of satisfaction from the system as well as from the garden.
This year I have put a lot of work into upgrading my garden watering system – from software to the controller, valves, pipes, and sprayers. It’s nice to know plants won’t die over the summer even if I forget or am too busy to hand-water them, and to know that seeds won’t dry out and fail to germinate because of a single missed watering. I’ve enjoyed a great summer/autumn harvest of tomatoes, eggplants, zucchinis, artichokes, eggplants, tomatoes, basil, coriander, mint, Vietnamese mint, radishes, silver beet, mustard, bok choi (notable failures were okra and potatoes – I’m not sure why they failed but at least I can be sure it wasn’t from a lack of water).
As well as running pipes and wires, I wanted to build my own controller – a device that automatically switches the water on and off. A typical controller allows you to set watering times for each day of the week. I wanted to go further and have an internet-connect controller that I could log into and change the settings remotely.
This post is mainly about the initial steps for the new system, and the old system it replaces. Part 2 will be about running the pipes, part 3 the controller hardware details, and part 4 will be the software details.
I hope these posts will help you set up or improve your watering system so that you can enjoy great results too.
The Old System (2014-2015)
The old system had two zones. Each one was controlled by a battery powered electronic timer connected to a tap. This worked ok but there were a few problems with it:
- It took up two taps which made it hard to use the taps for other things
- The set times were hard to change – I had to crouch in front of it and use 4 buttons while staring at 1 1x5cm LCD
- It was noisy while turning on and off, it took about 10 seconds as an internal tap was rotated
- Because there were only two zones, the runs of pipe were very long and the ends of the runs did not get sufficient pressure.
- The controllers never really attached to the taps well and would always drip.
Eventually when one of the timers stopped working I really got fed up with it. Only half the garden was being watered! And a month later the second timer stopped working too. Around the same time, someone I know who was using a similar system, came back from a holiday to discover their backyard flooded. The battery on their timer had gone flat but just before it died, it switched the water on one last time, never to switch it off again. By the time they got home, their water bill was over $1000. At $30 each for the timers (plus a $1000 water bill if you get unlucky), the money is better spent on a system that will last longer. So I decided to finally upgrade my system to use irrigation solenoid valves, which I’d seen my grandfather successfully using for a while. I decided to create my own controller so that I could internet-enable it and have better control than a regular off-the-shelf controller.
The New System (2016)
I decided to find a good set of solenoid valves first, and then figure out the pipes, wires and controller that I would need. I already had in mind to build my own controller, because the ones I saw in shops were overpriced and had limited functionality.
The valves I used are from Nymet, I bought a set of 5 on eBay for $65+$13 postage – search “Solenoid Valve Assembly”. Nymet deliver quickly and I am impressed with the product – they feel very solid, look good and seem like good value compared to the alternatives.
On receiving the valves, I connected the wires of one of them to 12V and heard a deep ‘clunk’ sound as the solenoid switched on. Next, I connected it to a tap and turned the tap on. No water came out. Applying 12V to the solenoid wires again resulted in water gushing out. So far so good.
Each valve has a manual override tap and a pressure control which is useful for testing the system before the controller is wired up, and adjusting the pressure for individual watering zones.
The set of valves included one master valve and four manifold valves. The master valve has one inlet and one outlet. The manifold valves include a built in ‘T’ section of pipe which joins together with the other valves, so they have a common input of water. Each one has a separate output. I think it’s useful to keep the valves together in one place, as shown below, and run pipes for each zone, and the control wires to this central point. You can plug it together however you like, though.
Stay tuned for part 2!