Automating your Irrigation in 2024

Tired of watering your garden by hand? Want to keep your food garden well-watered while you are away? After decades of this time-consuming gardening activity, I decided to automate the task, and found that with today's technology it is totally achievable and affordable for home gardeners. Here is what I learned.

My adventures with automating my irrigation started when I wanted to make sure that tomato plants in my hothouse would be irrigated while I was away on holidays in the middle of summer.

Water pressure is not the first thing people think of when talking about irrigation, but after some of my early irrigation attachments cracked under the pressure, I realised that I had to tackle a water pressure problem first.

Water pressure

Water pressure is measured in Kilo Pascals (kPa). We had our mains water pressure measured by a plumber. We live in Lindisfarne, Hobart, Tasmania, Australia, and it turns out that our water pressure can be up to 1200 KPa at times.

To put this in perspective, most manufacturers do not honour the warranty on washing machines if water pressure is over 500 kPa. It is good to know what your water pressure is when it comes to irrigation, because most irrigation drippers and drip-lines need a pressure of at least 50, but no more than around 300 kPa.

So my first step was to ask our plumber to install a pressure-reducer at the point where mains water enters our property. He installed one that limits the pressure at that point to 500 Kpa, but we can adjust it down if it needs to be lower by turning the knob (in the middle in the photo below). Cost including installation was $A250 (Feb 2015).

A simple automatic tap timer

After solving the pressure problem, I focused on buying an automatic tap timer for the irrigation of my hothouse.

After comparing automatic tap timers, focusing on sturdiness, easy of programming and flexibility of watering times and durations, I bought the unit in the photo below. This tap timer gets its power from a 9-volt battery.

The water coming out of our taps in southern Tasmania, Australia, is not dirty on average, so I decided to go for a simple setup (see photo below) without a separate filter. The timer is just straight onto the tap. The tap is open permanently.

This unit allows you to set one watering schedule, with great flexibility and ease.  In the hothouse I use drippers on poly pipe to get water to each pot and container.

I no longer have to water pots in my hothouse by hand. If I need to increase or decrease the irrigation time or frequency, this is an easy job that I do on the panel of the device.

The tap timer is programmed as follows …

• You set the time when watering should start (24-hour clock)
• You set the duration
• You set it to water on specific days of the week, or every day, every second or third day

The best time of the day to water gardens is early in the morning. At that time of day water that splashes onto leaves does not cause leaves to burn and evaporates soon after. This minimises chances of mildew and other diseases.

In the photo, above, you can see that the tricklers in my hothouse spread a fair amount of water. I found that having them on for just one minute per day was enough to keep my tomatoes well-watered, so I ended up with the following watering schedule:

 

On my return from my summer holiday I found that my tomato plants were healthy and doing well. Victory!

A tap timer with multiple watering schedules

With the automatic watering of my hothouse working properly, I decided that I was going to automate irrigation of other parts of my garden. I wanted to achieve the following:

• Water most or all of my garden early in the morning
• Have permanent hose connections so I no longer constantly connect/disconnect hoses leading to wear and tear on my connectors and leaks
• Minimise the time I spend watering my garden
• Ensure that watering continues while I am away

I have in my garden two overhead sprinklers. Another area has a weeper hose. Other areas have drip lines. For more on what these types of irrigation are see Improving your Irrigation on this blog. 

These irrigation methods spread water in different ways and at different rates, and different plants need different amounts of water, so I didn’t want to irrigate them all for the same amount of time. When I wrote up what I had and what I wanted to achieve, I ended up with the following watering schedule:

To automate this, I could buy six tap timers of the type discussed above, but then I found that I could do this with just one special water timer that allows for six watering schedules + one clever gadget called a water distributor.

Here is what I bought …

 

• On the left is a tap-timer that allows you to set up to six watering schedules. 

• On the right is a water distributor. It is a clever box that distributes water it receives from the tap timer to one of up to six hoses that can be connected to it.

The photo below shows the shady spot (the less UV on these plastic devices the better) where I installed the two boxes:

The system works as follows:

• The tap timer is attached to the tap, which is open permanently. 
• A hose runs from the tap timer to the water distributor. The tap timer allows water to flow to the distributor for up to six times and durations that you program into the tap timer.
• To the other end of the water distributor you connect up to six hoses (the orange connectors in the photo).
• The first time that the water reaches the water distributor, it will go to hose 1.
• When water stops flowing, the distributor automatically switches over to hose 2.
• Next time water arrives at the distributor, it goes into hose 2.
• The process is repeated until water has gone to all six hoses and then the distributor switches back to hose 1.

Whereas the tap timer is powered by batteries, in the water distributor a powerful spring is moved by water pressure – no battery needed!

The first time I tested this with just a few minutes of irrigation to three areas of my garden I was excited when everything worked according to plan. It was a joy to watch it in action, especially when I realised how much time it was going to save me in the future. 

Here is my watering schedule one more time:

Hose 1 starts irrigating at 6am for 30 minutes. Then there is a 5-minute break in which the water distributor changes over from Hose 1 to Hose 2. Then Hose 2 starts irrigating at 6.35. It irrigates for 30 minutes and switches off at 7.05am. Hose 3 starts 5 minutes later .... and so on.

Through a little window on top of the water distributor you can see a number. It is the number of the hose that will receive water next, when the tap timer supplies it.

People asked me 'Why didn't you put some of these areas on one and the same irrigation line?'. I didn't combine raspberries, blueberries (Hose 4), figs and apricot (Hose 5) into one irrigation line because the line would become too long. Plants at the end of the line would receive little or no water.

The tap-timer doesn’t allow you to mess up your times. For example, if you try to set the start time for Hose 2 at 6.20 (that is before Hose 1 finishes), the system doesn't allow you to do so.

My aim right from the start was to keep things simple so I understood what the system was meant to do and could keep an eye on things.

You can of course mess things up in other ways: if you connect Hose 2 to outlet 1 on the water distributor things will not work as expected! But once all connections are right, there is no need for further worry because you never disconnect them.

You don't have to have six hoses and garden areas to make this work. I started with just three hoses connected to my water distributor, and had three grey plastic caps on outlets I was not using - see photo of the water distributor above.

The system discussed here transports water through hoses at times and durations determined by you and it does not matter what irrigation method you use at the end of those hoses. Each can be different, and hose lengths can vary too.

Now let's add some 2020s technology

At an FGG visit to a food garden at Lenah Valley a few years ago host Marg M. introduced me to an Australian-designed tap-timer brand called LinkTap that takes all this to the next level.

Soon I was convinced of the superiority of this product. After starting with just one new LinkTap tap-timer to try things out, I phased out over time all three Gardena tap-timers and replaced them with new LinkTap tap-timers. 

Imagine a sudden downpour of rain in the evening that is so wonderful that there would be no need for automatic irrigation early the next morning.

With my old system I would have to go outside to where my tap timers are and switch them off manually. That is okay, but not great.

Now, I stay inside, open on my mobile my LinkTap app, and switch my three tap timers off by pressing their Pause button on my mobile.

Setting up and changing watering schedules is a breeze. No need to do them on a bit of paper or in a spreadsheet beforehand. I start the app on my laptop and make the changes there. Irrigation on Thursday is the same as on Tuesdays? Just copy Tuesday to Thursday. No need to press rubbery buttons for every day of the week while kneeling in front of your tap timer outside.

Here is a screen dump of the main LinkTap screen when opened on my mobile. Here I choose one of my three tap-timers Ferns, Vegs or ANZAC (after the peach tree in that area). Their performance can be monitored live and managed from my mobile or laptop.

My new tap-timers talk to a little gateway box that sits next to my modem/router. That gateway box talks to a worldwide LinkTap database that holds my watering schedules. I can see on my mobile what watering is taking place or what I have scheduled. I can change some of the times or change all of it on my mobile. I can do this wherever I happen to be in the world.

So what happens, you may ask, if this system goes off line. Won’t you be able to use your irrigation system? Yes, you will be able to use it. During an outage you just can’t make changes.

How many outages have there been in recent times? Just one very short one in the last three years and that was in the middle of the night when no one in Australia was using it.

Recommended brands of battery-operated irrigation devices

I have tried not to focus too much on brands up to this point because I wanted to discuss how these devices work regardless of what brand they are. There are many competing brands in this section of battery-operated tap timers and all of them work largely along the same lines.

Some tap timers allow you to enter a single watering schedule and for some people, it is all they need. Other people will need a tap-timer that allows you to enter multiple watering schedules.

Some tap-timers are easier to use than other ones. With most tap-timers you can only make changes or start/stop the system on the panel of the unit itself.

The brands that I have used and found to be really reliable are Gardena and LinkTap. I started with Gardena tap-timers, then after some years replaced them with LinkTap tap-timers, not because the Gardena units had failed, but because I found the LinkTap system easier to use and just as reliable.

There may by now be a Gardena app that allows you to manage your tap timers on your mobile. I found LinkTap to be so reliable and robust that I have not looked at other brands. LinkTap is an Australian-designed product. Batteries in LinkTap tap timers last a number of seasons and the system tells you when it is time to replace them.

Find out more about LinkTap tap timers here.
Find out more about Gardena automatic watering products here.

In regard to water distributors, the situation is different. I have not seen a credible competitor for the Gardena water distributor. It is a very clever, reliable device. I have three of them.

Mains-power operated irrigation systems

Decades ago the only way you could automate your irrigation was to connect a mains-powered irrigation controller with a number of solenoid valves that acted as taps. 

In a mains-powered solenoid system an irrigation controller unit is connected to 240-volt mains-power. From there 12-volt power lines go to a point in your garden where you have a tap. There the 12-volt lines are connected to solenoid valves that act like taps for your garden hoses. The 12-volt lines need to be put underground in conduit that is not going to be pierced by garden implements. 

Today irrigation systems using solenoids are widely used by farmers. You also see them in home gardens, but systems using battery-operated tap-timers (as described above) are now more widely used by home-gardeners.

A quick comparison of the two systems goes something like this:

During a food garden visit at Otago in October 2024 hosts Geoff and Gemma showed their solenoid irrigation system.

Here is a picture of their irrigation controller:

The use of this panel and the capabilities of the system are similar to what you saw above for battery-operated systems.

Below is the spot in their garden where the 12-volt lines that come from their irrigation controller are connected to six solenoid valves (the ducks were keen to be in the photo):

 

When you take the covers around the tap away, you see six solenoid valves and six water pipes leading away from the tap area to the various parts of their garden:

 

Geoff installed this system himself. He spent less than $500 on equipment and cables (2022 prices). He knows what he is doing, because he installed a solenoid system in just about every garden where he lived.

Good examples of mains-powered irrigation systems can be found here:

• Rain Bird - the brand used by Geoff (see irrigation controller photo above) 
• Reece – a company that sells Rain Bird and installs irrigation systems

After many years of automated irrigation ……

I only manually water pots and spots in our garden that can’t be reached by the irrigation, and that is an easy enjoyable task. All the other irrigation is done automatically early in the morning. Over time I have fine-tuned irrigation times. I switch the timers off after rain, and then on again a few days later. 

As the seasons turn, I increase or decrease irrigation times or irrigate twice a week instead of once. It is all just a matter of adjusting watering schedules, not being in the garden for hours to keep everything watered. I love it!

But technology can fail. One early morning with blue skies and no rain during the night I got up, looked out of our bedroom window and noticed that the concrete path to our clothes line was entirely wet. Knowing that irrigation had been on in that part of the garden at 6am, I decided to check. I found that the terminator (the 'end bit') at the end of a drip line had been blown off. All the water had flown down the concrete path. Nothing had been irrigated, except the lawn down that path.

It's great to have a high-tech automated watering system that you can adjust while being away from home. Install it, enjoy it, cherish the time it saves you by watering everything automatically, but do not blindly trust that everything will always work without an occasional watchful eye!

I hope this introduction to automated irrigation helped you making up your mind about it. Yes, there is some work involved in setting one up, but the investment in time and money is really worth it!


Max Bee