Every spring, new growers are entering the world of vegetable production with dreams of amazing flavours, some quality time in the garden with their kids, and a bounty of fresh wholesome vegetables. They lay out the plans for their vegetable vision, acquire some gardening equipment, break ground, and plant a collection of their favourite crops. All is going according to plan, but just as they are about to sit back and put their feet up, they realize the hidden reality of vegetable growing. They wanted a vegetable garden to help them escape their ties to the grocery store, eat the best food possible, and (if they're really in deep like yours truly) maybe even quit their job to claim ultimate independence...but that self-sufficiency DREAM is more like self-sufficiency PRISON. Everything in the garden seems to need them...all the time! They find themselves constantly having to choose between turning down social invitations so they can serve their garden, or letting their garden duties slide in order to maintain their other commitments. The only two paths seem to be to become a vegetable hermit (been there done that 😄) or squander all hope of self-sufficiency and trudge back to the grocery store with their wallet.
Most people in this position who think critically about their gardening work will realize that their primary tasks, at least the ones that demand constant unfailing attention, are weed management and watering. These are the two tasks most guilty of turning your gardening dream into a gardening prison. If we can eliminate the time we spend on weeding and watering, we're just left with planting, harvesting, and a little trellising and pruning here and there. Suddenly our garden starts to look a lot less like a prison and more like an asset!
I've touched on the basics of our weed management strategy in a previous post, so if that's your struggle, you can head here to read more about winning the war on weeds. I'll devote the rest of this post to the subject of watering, but not just any style of watering. In an ideal world, we want a solution that will deliver water to the roots of our vegetable crops with the highest efficiency and the lowest amount of labour on our part, and for this, drip irrigation systems stand out far above the rest.
When I Drip, You Drip, We Drip
One drip on its own won't accomplish much in your garden, but many drips serving a collection of garden beds in unison can effectively and very efficiently apply water right where it needs to be, at the base of your plants. Each drip line you place in your garden is like a perfectly focused gardener keenly applying water in just the right place for just the right amount of time. It's a beautiful thing in a dry climate like ours, and I owe so much of our success with vegetables to the devoted service of our drip irrigation systems on many different plots over the last decade. So today, I'm going to honour those 10 years of service, with an introduction to some drip irrigation basics. If you're about to build a drip system of your own, you'll be glad to hear that the seemingly complex system can really be boiled down to just four components: a water source, a control centre, supply lines, and drip lines. Let's address each component in a bit more detail.
The Water Source
Most of you will be starting your drip system installation at a hose bib attached to a house, garage, or other out building on your property. You've likely got high pressure water coming from this hose bib and an ample supply to serve your garden, but we need to get that water to your garden somehow. My top two choices to move this high pressure water are a solid rubber hose (not vinyl) or a 3/4 inch polyethylene pipe. The rubber hose is the more flexible and easier to install option if you don't have a long distance to travel. The polyethylene pipe is the more durable and cheaper option, but the installation is a bit more complex and better suited to semi-permanent scenarios where you won't want to be moving the lines often.
Before you attach the rubber hose or polyethylene pipe to the hose bib, I recommend adding a hose Y splitter valve so the line you are setting up to serve your garden can remain dedicated to that purpose at all times. If you need water from this hose bib for another purpose, you can just grab it from the second valve on the splitter.
On our borrowed land, we always install a water meter as well so we can track the amount of water used for our garden and reimburse the homeowner for the cost of that water. The idea of metering your garden water is not a bad idea though, even if you're not borrowing your land. It can really help you clarify the costs and rewards of your gardening efforts.
The Control Centre
To use our water supply effectively in a drip system, we need to reduce the water pressure to a more appropriate level and set up a timer to automatically turn the system on and off at the right times to deliver the appropriate amount of water to our garden while we're going about the rest of our life. Both of these tasks are accomplished in the control centre. It's also standard practice to add a filter here too in order to prevent any debris from potentially sneaking into your drip system and clogging emitters.
So there are your three main components of your control centre: a timer, water filter, and pressure regulator, plus a few adaptors to connect these three components. The order in which you connect these three components can vary depending on unique circumstances on your site, but the filter should always be before the pressure regulator.
The control centre should be located as close to the edge of your garden as possible with easy access. After this system is set up, you won't need to lug a hose around your garden anymore, but you will need to visit your water timer once in a while to make adjustments, so make sure that task is easy. The components we've used for our control centre have had no trouble handling exposure to rain, but some timers benefit from being shaded from the sun, and everything here can of course be damaged if water was to freeze internally, assume that you'll need to remove this control centre every fall if you're blessed with freezing temperatures for a any part of your year.
The Supply Lines
After the control centre has done the jobs of reducing the water pressure and turning the water on and off at the right time, we need to deliver that water to our beds with one or more supply lines. These supply lines are not dripping any water yet. They are just delivering the low pressure water to our garden beds to be distributed.
The best pipe for this application is polyethylene pipe, and my preference is the 3/4 inch pipe diameter to minimize pressure losses along the way. These supply lines need to neatly run by the edge of each of your garden beds, so here is where you realize one of the benefits of having a standardized bed size and rectangular bed layout. The simplest scenario is that you just have one supply line running down one side of one row of garden beds as shown below.
If your garden bed layout is more complicated than this, don't fret. Drip systems are actually very adaptable to different sizes and shapes, much more so than overhead irrigation systems. Your supply line can be extended in any direction. Just remember that you are dealing with low pressure water after your control centre, so if your garden is quite expansive, make an effort minimize the distance that your low pressure water has to travel.
The Drip Lines
All that's left at this point is to tap into that convenient supply of water that you are delivering to each garden bed and efficiently deposit those drips of water right where they need to be. I like to give every bed its own unique line that can be removed or shut off as needed without disrupting the irrigation for the rest of the garden.
The best products to accomplish the task of distributing the water are drip tape and drip tubing. Both products have evenly spaced drip emitters that distribute water evenly along their path, but there are a couple of differences worth noting.
Drip tape has a lower cost per linear foot and is easier to roll out and roll up when you need it out of the way. These characteristics make it a great choice for long straight beds. Drip tape can kink very easily so it's not the best fit if you know you'll want your drip lines to be turning lots of corners.
Drip tubing has a higher cost per linear foot and it's less easy to move around, but it's much more flexible, allowing it to turn corners easily without interrupting the flow of water. This makes it a great fit for smaller and shorter garden beds.
Beyond those differences, there are a lot of similarities between these two types of drip line.
Both types of drip line can be installed with shut off valves at each bed so the water supply can be turned off when a bed is not in use.
Both types of drip line will have a standard flow rate from their emitters that can be used to determine the amount of time the system will need to be turned on to deliver an inch of water to your garden beds.
Both types of drip lin are simply pinned to the surface of the bed so they don't wander around accidentally.
Both types of drip lines easily slip away into the background of your garden, quietly performing their task while you do other things in the garden, go to work, sleep, or even leave home for a holiday!
Are you ready to build your own drip system?
There's a lot to love about drip systems once you get to know them, but there's also quite a bit to sort out when you're new to this world. While I've introduced the four basic elements here, there are surely a number of questions still cycling through your mind. Know that there are answers to your questions and the answers may not be as complicated as you might think. I often find the hesitancy that any new growers feel about getting started with drip systems is just due to unfamiliarity. If you haven't worked with any of these components or fasteners before, it's logical for the number of unknowns to feel overwhelming, but that unfamiliar world becomes a lot more comfortable when you've seen someone perform all the necessary tasks, and that's why I'm here. If you'd appreciate detailed instructions on designing and assembling your system, enroll in the Seed to Table course and make the process as easy as possible. A short time from now, you could be crossing that garden watering task off your to-do list once and for all and entering the wonderful world of automated drip irrigation.