My friend was describing a plan he had to build a hanging garden from surplus rain gutters. I thought the idea was great and decided to build my own hanging ebb and flow hydroponics.
Ebb and flow hydroponics
Ebb and flow are the two different phases of oceanic tides, or any other similar movement of water. In hydroponics, the term is used to differentiate systems from the continuous flow systems. The ebb and flow are usually the more favoured option by diy builders, as the one of the most simple system is a really easy build and provides very little risk in water damages.
In a continuous flow hydroponic system, a nutrient rich water is constantly flowing in the system. We have a herb box that is a continuous flow system, but it only fits three plants To utilize our greenhouse -like balcony, I decided to build a hydroponic system for herbs for the summer.
Building hanging ebb and flow hydroponics
It has taken me over a year to complete the setup. I heard and acted on the initial idea already in summer 2017, but I had some issues in completing it. I used it to grow chilies and cilantro, but I never managed to build the watering system so most of the plants in it withered away. (The mint survived, its a tough one)
The vessel
I started by buying cheap plastic rain gutters. The gutters were sold in two meter pieces. I bought two gutters and four end plugs/terminators. To hang the gutters, I bought some relatively light stainless steel chain and some s-hooks to tie the chain together.
The installation was easy, just screw two loops in the roof support struts, pull the chains through and check the level of the gutters. Plug in the end terminators and voilá! Everything was in place.
The plastic gutters are really light. They are actually so light, that they have problems staying in place. They easily tip over if not careful.
Manual watering
So I didn’t install the watering system to begin with. I used a watering can to water the wire potted herbs. The totally glass enclosed balcony got so hot, that the water evaporated darn quickly from the gutter and the plants so I decided to look into putting some growth medium to slow the natural evaporation and buffer the water.
Growth medium
When using the gutters with manual watering, I filled them with soil. A store bought, ready fertilized herb soil. It worked like a charm, it allowed me to water the plants only once a day and still keep them alive. I filled the gutters with the soil while they were hanging, and naturally spilled some on the white couch below. Naturally this wasn’t very optimal.
Now that I’ve setup the automated water system, I decided to remove the soil as a growth medium. I’m thinking of using coconut fiber or gravel to increase water retention in the gutters after the pump turns off.
Automated water system and hosing
The main reason for putting off the watering system was finding the right pump. I wasn’t willing to spend too much money, I didn’t watt a 500W pump, but it had to have a head height of at least 2,5 meters. Sadly, I wasn’t able to find one, so I let it be.
I had completely forgetten about the pump systems, until last night I was sitting at our balcony and was looking at the gutters with dried and dead cilantros (the mint was still going strong). I decided to google again for a pump.
And this is what I found! Only 50W and with head height of 2,3 m. And it only cost like 30 euros! So off to the shop I went and bought some garden hose connectors, a huge bucket and hose clamps. I also got the great opprtunity to buy a new 25mm drill bit for my adaptable hole drill.
Below are some photos of the setup. The installation was very straight forward, drill the holes, screw in the garden hose connectors as inlets and attach the hoses. Connect the fountain pump and put it in the bucket.
In addition to the hosing, I had to glue the end plugs of the gutters in place, as they leaked a bit. I used a heavy duty pattex glue.
I’m still planning to connect the input hose to the drainage hose to make the bunch a bit sturdier and nicer looking.
Current running method
The pump is currently plugged in a socket that I can control with a switch. I flip the switch and the pump begins to pump the water up. The first drain from the upper gutter is relatively slow to drain, whereas the final drainage tube empties the lower gutter in a vortex.
But I need to automate this. Work still to be done is to time the amount of time it takes the pump to fill the system. Turn if off and time how long it takes the system to drain itself. Add some safety margins and create a program to a short cycle timer.
I.e. If the system fills up in 30s and drains in 45s, setup a program of 25s on – 60s off.
Electronics
A short cycle timer is a timer that does just what I described: It cycles a power outlet on/off successively. Some timers can be adjusted between 0,1s to 99h between each change in state. My biggest challenge was to identify what the timer was called. Googleing “240V timer” and “240V digital timer” just gave me products, that could turn the pump on/off once a day, although in a varied weekly schedule.
In finnish, the timer is called “pulssiajastin” or a pulse timer. I eventually found some units that seemed to suit my needs, and this time I decided to buy one from here.
So now I’m waiting for the timer to arrive, install that and then reap the benefits! I also aim to use the system to discard the nutrient rich water from my aquarium to feed my herbs!
The verdict so far
It system works. The pump is quite noisy, as I haven’t yet filled the bucket to cover the pump – the sound is dampened significantly by the water. And how do they compare to my friend who had the original idea? To this day, he hasn’t gotten around to building it.
Just a thought, But if you put an elbow on the top line the hose wouldn’t stick out so much. The drain line can go strait down and all hanging vessels can be level as water will always flow from highest point (entry) to lowest point (drain). No reason to pitch the planters.