I had every intention of putting a drip irrigation system in our garden this year. I’ve done a ton of research. I reorganized our beds to prepare them for ideal drip emitter spacing and line configuration. I even wrote about it in these blogs Homestead Goal Setting – Irrigation, Irrigation Education – Clear as Mud!, and Vegetable Garden Layout and Rotation Plan.
Yet something kept holding me back from moving forward. I like to visualize things before I do them and every time I saw myself rolling out drip irrigation lines in my beds, my stomach turned. You know that feeling you get when you suddenly change elevation, like on a roller coaster or when cliff jumping into a river? If sought intentionally, that feeling is fun and exciting. But when I get that in normal life, I take it as a warning that something’s not right.
After a few weeks of side-lining my irrigation plans, the gut feeling finally started to make its way to my brain as useful thoughts. I ordered a couple models of manual siphons to see how hard it would be to get the water flowing out of our uphill pond down to our garden. I also wanted to find out the gallons per minute (GPM) flow rate without a pump to figure out exactly how much of a pump we’d need to run our irrigation system. We wanted to to use an electric pump so we can power it from our solar panels. But the pump salesmen suggested we would need a gas pump or to install a 220 volt outlet at our pond to run a more powerful electric pump. Neither of those ideas sound right to me.
The hand siphons turned out to be useless. They were just too flimsy to connect to a 100 foot heavy duty hose and create reliable pressure. But, in trying, I realized I could use another hose as my siphon. I ran a hose from our house spigot to my garden, then ran a hose from our garden up to our pond. I put the hose about 5 feet into the pond to simulate our worst-case scenario draw. I then used a spigot splitter to connect the two hoses so I would have a shut-off valve in the garden without walking to the house to turn the water off (about 175 feet). I turned on the hose at the house and went to the garden. When I was sure the water had enough time to run the length to the pond, I turned off the water at the splitter and disconnected the pond hose from the splitter.
I put the pond hose in a 55 gallon drum and when the water started flowing into the barrel, I started the stopwatch on my phone. It took almost 17 minutes for the drum to fill. It worked out to about 3.2 gallons per minute without a pump. That flow rate comes out to about 192 gallons per hour which would be sufficient flow rate to run drip irrigation without a pump. With drip line, you get a choice of drip emitters flow rates and spacing. So, for example, if I wanted my emitters spaced 12 inches apart, and I chose .6 gph emitters, I could supply 320 feet of drip line with my gravity fed flow from my upper pond (192 gph total flow / .6 gph needed to supply each emitter = 320 emitters spaced 1′ apart). If I increased the spacing to 18 inches, I could run a 480 foot system.
Pressure also plays a role in figuring out how long of a line you can run. So, before you go running lines based solely on flow rate, you need to figure out your PSI at the point where the water will enter the irrigation system. The easiest way to do this is with a gauge. But if you don’t have one, there are a couple other tricks you can use to get an estimate using elevation.
As I learned from Irrigation Tutorials every foot of elevation drop is a pressure change of 0.433 psi. So, if you know the elevation difference between your water source and your outlet, you can figure it out by multiplying the elevation change by 0.433. I have at least a 25 drop in elevation from my pond to my garden, so I have at least 10.8 psi.
I also found another method that has you elevate the hose end until the water stops flowing and then divide the height by 2.31. That one didn’t work for me because the hose started to fold over at about 8 feet. But if I didn’t know my elevation change and could have pushed the hose up the side of a two story house to about 25 feet tall and seen the water stop flowing, then I would have divided 25/2.31 to come up with 10.8 PSI same as I figured using my elevation change. Just for kicks you could try this on your rain barrel.
Once you have your GPM and your PSI, then you can figure out how much of a drip system you can actually run. Different dripline manufacturers have different installation guidelines. The table below is from Rain Bird. Based on this chart, with 10 PSI and 18″ spacing, with 0.6 emitters, I can run 175 feet of line just using the flow and pressure generated by gravity, the hose, and the initial backflow from the house-hose siphon technique. No pump necessary! Since I already know I have the GPM to run a 480 feet of dripline, my low PSI is the limiting factor in run length.
If I want to run a longer line, then I need more PSI, not more GPM. I have found plenty of highly rated pumps available for under $100 that can run on battery or a normal electrical outlet at 40 PSI and 3.5 GPH or better. I haven’t actually tested this theory, but if product specifications and consumer ratings can be trusted, then this would solve my pump issue.
But, that sinking feeling in my stomach still lingers when I imagine rolling out the line. It just seems at odds with the human-scale operation we are trying to create here at the reLuxe Ranch. Right now our operation is manually intensive because our edible landscape is young and needs time to establish and our soil still needs a lot of work. Plus, we dedicate a lot of time to learning since we have only been doing this for three years.
Yet, three years from now, that won’t be the case. By then our perennial systems will be well underway, our pastures established, and our connections between systems more tightly knit. And hand watering, even a much larger garden than we have now would be no trouble at all.
As we celebrated the 1 year anniversary of my dad’s 55mm brain bleed and his road to recovery on Friday night, I realized how much of an impact that event had over my outlook. I spent the better part of last year worried about how I would get everything done that needed to get done. In fact, though, I got more done than I had on my schedule even before my dad had any health problems.
Feedback loops are something discussed often in reference to the environment. For example, it’s not just CO2 emissions that are a problem, but rising ocean temperatures and thawing permafrost as a result of those emissions, that then make the original problems even worse. You mess with one thing and everything changes. But feedback loops work in a positive direction as well.
Learning to care for my dad may not have been a homestead skill I set out to acquire, but in doing so, it led me to refine my animal care procedures and look for corners to cut and ways to be more efficient in other areas. As a result, I actually have more available time now than I did before – even with caring for my dad.
Also, the more we homestead, the better we get at homesteading. For example, it used to take me weeks to plan and build and animal shelter. And most of my early attempts were short lived and had to be torn down and reconstructed later. Now I can plan and put up a durable shelter using a mix of free-sourced, scrap materials, and a few key purchases in a couple of days. I am much stronger now from three years of homesteading, so I can dig a deep hole in rock hard soil in a few minutes and then dig 50 more without fatiguing. When we started I could only dig a few holes a day and would be totally exhausted. It took me months to plan our first garden, now it takes me hours. I think you get the point.
The conditions that made an irrigation system seem like a must, have already been solved. So, I did some time trials to see how long it would take if I had to water the entire garden at a rate of 1 gallon of water per square foot. Using a watering can, it would take me about 5 hours. But, I’m a polyculture person, which means there is no way on earth I could stand around watering for 5 hours. In practice, I’d do 1-2 hours of water a day, probably split between morning and night and spread it out over several days. Even last year, if I had known how little time it actually took to water my garden effectively, I could have kept up with this schedule. I already hand water newly seeded beds and transplants daily, so some of that watering is already accounted for in my planned time. And this is a worst-case scenario, assuming no rain. That will happen a few times over the growing season, but probably not for three months in a row like it did last year.
After making all these calculations and looking back on last year, I decided an irrigation system isn’t necessary. Instead, I used that hose siphon trick covered previously, and then I connected the pond hose to a ball valve. The ball valve required a female hose connection, but I needed a male hose connection to join the hoses and create a pressure siphon. So I needed to buy a female to female connector to pressurize the hose. They cost $6. I had the hose and the ball valve, but if I had to buy them, they would have cost about $60.
When the ball valve floats closes, then the hose stays pressurized. So I don’t have to drag a hose from my house every time I want to siphon pond water. As I use the water, the valve opens and the pond water starts running again. This means I don’t need to pressurize the system again unless I remove the hose from the pond for some reason.
I first learned about using ball valves when I worked with Marjory Wildcraft to write an eBook on Animal Watering Systems. I reproduced some of her systems on my homestead and documented the procedures. You can get a free copy of the eBook by signing up here:
Right now I am just using the 55 gallon barrel in the header photo as “proof of concept”, but I plan to either string together a series of 55 gallon barrels or use some IBC totes to hold more water. I can get everything I need for under $100 around here. If I am only watering for about an hour at a time a 55 gallon barrel will work fine since I’ll get 192 gallons from it per hour, plus the 55 gallons in it when I start watering. However, by having more water storage, I can also grow more water hyacinth and duck weed.
My ducks and chickens love the stuff so it’s hard to keep in my ponds because they eat it all up. I may also try to work minnows into the system as another feed source for the ducks and chickens.
Now, when I imagine myself hand watering with pond water filtered through water hyacinth, duck weed, and possible inhabited by minnows, I just feel happy. I really love to water plants. It gives me a chance to admire and wonder at them. It’s almost like a meditation that forces me to slow down and simply enjoy being in my garden. If you are short on time, irrigation systems are great. But, for us, right now, hand-watering makes more sense.