Introduction: Fertigation

This is an add on for an irrigation system, that delivers liquid fertilizer.
Here are a couple youtube vids showing how it works.
Im using about 400ml of a seasol like liquid fertilizer in a 1.25L bottle for 40 plants.

Step 1: Add Conections to the Bottle.

Cut the barbs off one side of two small hose (I used 6mm) conectors.
Drill tight holes in the lid and glue them in.
Add a short and long piece of hose to the inside.

Step 2: Add Conections to Your Irrigation System

Cut the hose after your tap timer or control valve.

Add a tap with enough room either side to insert small barbed connectors.

Insert barbed connectors either side of the tap you put in.

Put a loop of thin hose on the barbed connectors.

Step 3: Connect the Bottle

Cut the thin hose and connect the timmer side hose to the bottle barbed connector that has the longer hose inside.
The other hose on the garden side goes to the bottle barbed connector with the short hose inside.

Step 4: Try It, Calibrate the Flow.

Ok so now it should be good to go. You want the flow to be slow through the bottle so it disperses the fertilizer evenly over your plants.

To do this the tap you put in should be turned slightly so it creates a pressure difference and creates flow through the bottle from bottom to top.

The photo of the diluted mix in the bottle was after running for 20mins. I was happy with that delivery rate.

Remember to use a pressure reducer as recomended for dripper systems so your bottle will hold up ok.

Step 5: UPDATE!

I have replaced tge pet soda bottle with sprayer bottle. its working really well. plants are thriving!

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    7 years ago

    Nice idea. Have you considered simplifying the set up with a Venturi style setup to control dilution?


    Reply 7 years ago

    Yeah Ive considered it. There are venturi products out for high prices. I just wanted to make something where I can add a mesured amount of fertilizer for a watering session.
    My concern with a diy venturi is the back pressure may be to high and water goes the wrong way through the fertilizer line. Benifit is obviously a bulk volume can be connected for many watering sessions, disadvantage is the complexity and ability to DIY.
    I had considered an arduino dosing pump into mixing resivour. But this build only took a couple hrs and works great.