Introduction: Inverted Sprinkler Experiment

I live in Dallas, Texas and I like to have a garden. There's nothing better than growing your own tomatoes, squash, cucumbers, beans, peppers of all sorts and my favorite, eggplant. Notice I didn't say I like to work in the garden, but I like to have one. Gardens equal work and I don't have a lot of extra time outside of my kids and work to put into the garden. So I come up with all kinds of ways to put my laziness, I mean my imagination, to use in coming up with ways to automate repetitive gardening tasks.

Dallas is not always a fun place to be outside...think 105 degrees with 60% humidity. All of that heat and light is good for the plants, but the ground dries up very fast. So much so, that I usually have to water every day or every other day for long periods of time.

I say all of this to make a case against soaker hoses.  While soaker hoses are great at delivering water, it's difficult to drench a bed in a reasonable amount of time. Also, in the Texas heat, hoses break ALL of the time. Nothing more annoying than repairing a hose with streams of sweat down your face and in your eyes.

I like sprinkler systems, but I feel like they just speed up the eventually water evaporation process, by misting the water and shooting it up in the air...you're free my little H2O friends, return to the sky and go be nimble somewhere else.

So, I thought I would try my own version of sprinklers that got the water to the ground faster. I looked over the Instructables site and couldn't believe no one else had done this, and maybe I'm missing it, but I thought why not water my garden like a large farm and came up with the inverted sprinkler experiment.

Step 1: Design: So Many Options to Explore

As you can imagine, this system isn't all that complicated, but there are a number of variables that I couldn't really understand until the system was completed. The main problem is how wide is the cone of the sprinkler when gravity is mixed with water pressure and height from the ground. I did some tests using a garden hose and a scrap piece of PVC and the appropriate attachments which included one sprinkler head. The example worked but it only told me about 1 sprinkler, not the 5 or 6 that I guessed I would need. Speaking of sprinkler heads, should I use a popup or a bush sprinkler and of this options, which brand should I use be cause my guess is that the angle that the water is ejected from the sprinkler head varies from Vendor A and Vendor B. Also, will turning these devices upside down screw with any of the functionality to the point of failure? I dunno. Uhmm all I know to do is just try it out and see (that's my favorite part of projects like this; trying to navigate the best solution by using prior knowledge and through a little research).

So after my head was reached the brink of an explosive aneurism, I finally just drew a sketch and started at the basic point of how the PVC would fit together to create a pressurized environment.

It's a straight forward design except I had learned from previous dabbles in PVC that the weight of the pipes are pretty high, so I figured I needed some supports which should be longer than the end supports so that the ends could be barrier or even put a brick or stone underneath the supports to keep them stable. The legs will be a part of the plumbing, so they will fill up with water giving them some weight and probably a bit more stability. If sag is a big problem, you could build a wood support and the attach the PVC to the wood. This could even become a trellis! Dual purpose is always rewarding.

Controlling the pressure from the source seemed like a possible way to affect what I'm calling the cone angle of the spray.

Step 2: Some Items I Needed

  • Some sort of scrap wood or treated wood or any sturdy, durable support
  • X number of feet of 3/4" PVC
  • Some regular T connections for the center supports
  • Some threaded T connections for the sprinkler heads
  • End caps for the support and the opposite end of the supply
  • Threaded connection for the source hose
  • A flexible piece of hose
  • Hose-end converter (not shown)
  • Pipe brackets to hold the main body in place
  • Sprinkler heads (not shown)
  • Risers to connect the sprinkler heads
  • PVC primer and glue
  • Maybe most of all, a little one eager to help

Step 3: Turn a Sketch Into a Thing - Part 1

The end supports were 'eye-balled' for their length. I had no idea how any of this was going to work, so I made the supports longer than I thought necessary, leaving me room to cut (easier to cut, than add to). Then I just attached to supports to the planter.

Step 4: Turn a Sketch Into a Thing - Part 2

I measured my support span and then made some more guesses about where each support and sprinkler should go. Dry fit it together  and then it was time to glue.

This is the part that my daughter wanted to help with more than anything and I was the most nervous for her to be around because the primer and glue are so toxic. In a well ventilated area (my openned garage), I ended up holding the PVC and rotating it while she brushed the primer on. She like it because its purple. I figured no matter how sloppy it was, it would sun fade and no harm done.

Step 5: Center System & Install

Set the support in place and attach the system to the support. I just used some 2 1/2" wood screws.

Step 6: Connect the Water Supply

Connect the short hose to the threaded end of the PVC and the other to the supply line. This was one of those moments when I realized I didn't think of everything. My supply was male and so was the flexible hose...at least I had a spare converter in my pile of everything.

Step 7: Cross Your Fingures, Test, Modify & Do It Again Next Weekend!

Try 1:


Try 2:

 

One concern that I've had a hard time trying address is I don't think it's a good idea to spew pressurized water onto fragile leaves. If the planter box was empty, I could plant the seedlings in such a way as to avoid the majority of the force, but given that this box already has plants in it, the results will have to be looked at as a learning experience if something were to go wrong. Maybe instead of having a single line of sprinklers down the middle, there should 4 or so sprinklers running down each side with 180 degree heads that spray from the side towards the middle. Hmm.

I suspect that both types of sprinkler heads will have a value depending on the types of plants, size of box and water pressure.

I plan on making a few more of these and if anyone is interested, I'll post my results.

It's hard to tell from the video, but as you might suspect, different heads give different results. My favorites are the popup heads and the 360 bush sprayer heads. I realize this just an upside down sprinkler system, but I really enjoy the process of creating things and I had fun sharing my ideas with you. Happy making!

P.S. The whole project cost about $30 and was completed in about 3 hours

Step 8: End of Next Weekend

So I repeated the process and didn't find any huge stumbling blocks. A new question about pressure arose, given that there are now 10 heads for 1 sprinkler zone, but I think that increasing the time more than makes up for the lack of pressure. Below is a video of the whole system: