Hacking into the Irri-Gator

Every once in a while, my husband accidentally runs something over with the lawn mower, usually because the grass has grown so long we’ve both forgotten what might be under it. Earlier this year he got a little too close to the corner of the garden, and my Irri-Gator pressure regulator ended up under the blades. Thankfully I had a spare one. I kept the remnants of the broken one because one never knows when such things will come in handy. And handy it was!

Before I worked at Johnny’s, I purchased the Irri-Gator system from them, and in my few years of gardening I’ve enjoyed using it. I’ve laid out my garden with it in mind, so all of the rows have tubing along them and all of my plants can get enough water. It is under my black landscaping fabric, which protects it from the UV rays. Watering hasn’t yet been an issue this summer, but it is starting to get hot and we don’t always get a thunderstorm, so I’ve started using it intermittently.

One thing that I like about the Irri-Gator is that I can use my hose timer to just “set it and forget it” (to quote a certain infomercial). One thing that’s always made me wonder, though, is whether there is a way to get the Irri-Gator to distribute liquid fertilizer throughout my garden. Other watering systems offer this option – Johnny’s offers a fertilizer injection system that you can attach to a sprinkler, for example, but the low water pressure used by the Irri-Gator is incompatible with it. So that got me searching on the web. I did find a system that can be hooked into the Irri-Gator or similar systems, but I’m pinching pennies this summer (we’re buying a woodstove and chimney plus cord wood, so we can stop using oil as our sole home heating source) and the $50 plus shipping just seemed like too much for such a simple thing. So I got to thinking – there has to be a way I can fashion such a thing cheaply at home.

I did consider that all of the fertilizer might stay close to where I have the Irri-Gator connected to the hose. I can live with giant onions if that is the case, and I can always reconfigure the attachment to better accommodate other areas of the garden. Other liquids disperse pretty well in water, and I think that the fertilizer will be spread out pretty well through the garden.

A couple of Sundays ago, I wandered my local Agway for a while and found a hose end sprayer which appeared to be made up of component parts that I could separate. The one I chose has a dial on top to regulate the ratio of fertilizer-per-gallon of water that passes through, and it sucks the fertilizer into the water going through the sprayer, rather than mixing the two within the container. I purchased two, just in case I could splice parts and end up with a hose end on both sides, and I also purchased a female-to-male hose adapter, so I could hook it to the system if that worked. I hoped that I could just change some parts around, attach the fertilizer sprayer between the hose and the Irri-Gator’s pressure regulator, and go.

Fertilizer Sprayer, converted
Alas, that did not exactly work out according to plan.

The sprayer I purchased was injection molded plastic, and, while I could get it somewhat apart, the hose attachment end and the sprayer end were firmly attached as one solid piece. However, I found another way as I took it apart. The sprayer nozzle opening, behind the adjustable attachment that allows you to vary the spray, is the perfect size to connect a piece of aquarium air tubing, of which I have plenty for my fish tank. I attached that and dug through my box of Irri-Gator spare parts. I found the broken regulator, which had a male end, which could fasten to the pressure regulator, and had nothing blocking the way for water to flow through in reverse. The broken female end held snug one of the Irri-Gator’s tee connectors, but it did pop back out with little coaxing. To the air tubing I tightly taped a piece of Irri-Gator tubing (sans irrigation holes), and connected that to the other end of the tee. I blocked off the side connection on the tee, as it was unnecessary (I just didn’t have any straight connectors – a straight connector would be perfect for this application, too).

Air Tube Connection
And then I tested. Things went pretty well. I filled the sprayer vessel with TerraCycle’s worm poop liquid fertilizer, which I had left from last summer, and set the sprayer to it’s highest fertilizer:water setting. I turned on the hose and it started going. It worked – but there were a few bugs to work out.

Tee Connection
First of all, the heavy hose tipped the sprayer vessel over when I turned on the water. That was an easy fix – prop it up with some rocks. Then there were some leaks. Water was spurting out from around my tee joint to the broken regulator connection, and also coming out of the broken regulator through a small hole in its side, which probably adjusted for pressure when the regulator was whole. So back to Agway I went.

I returned the extra sprayer and adapter, and picked up a tube of silicone sealant/caulking and a roll of Gorilla Tape. After allowing my Frankenstein sprayer to dry, I caulked the tee into the broken regulator, and caulked the small hole in the regulator. I shortened the length of the Irri-Gator tubing that I’d connected to the air tubing, and re-taped that connection. I let everything dry for a couple of days and tested again.

Connection to the Irri-Gator
It worked pretty well. I adjusted the fertilizer to a lower setting but the uptake wasn’t quite as thorough – there was still quite a bit left in the vessel at the end of my test. Also, the taped connection leaked quite a bit – obviously the tape isn’t the best solution. Next I am going to try caulking that connection and see how that works. There are a few more steps to be taken to perfect my device, but I’m excited – my theory worked, and so far it’s only cost me about $15 plus some old spare parts. And I can forgive my husband for running over the Irri-Gator with the lawn mower.