Autoponic Vertical Garden BENEFITS:
-Allowing for high density yields and shorter growth cycles
-Reducing resource consumption - water, fertilizer and space
-Labor saving - no weeds or soil to till
-Higher consistency of crops with great tasting results
-Maintained by micro-controller (Arduino)
-Watering cycles - monitor and auto refill levels
-pH - monitor and correct
-Connected through EasyIoT to monitor plants via ESP8266 over wifi
Way over 2600 years ago, a great king named Nebuchadnezzar built the Hanging Gardens of Babylon....the first Hydroponic Garden. We've came along way since then, but the basics are still the same.
Hydroponics is a subset of hydroculture, the method of growing plants without soil, using mineral nutrient solutions in a water solvent. Terrestrial plants may be grown with only their roots exposed to the mineral solution, or the roots may be supported by an inert medium, such as perlite or gravel. The nutrients in hydroponics can be from fish waste, duck manure, or chemical fertilizer. Many different civilizations from the beginning of time have relied on hydroponics for growing plants, such as the early Mexican and Egyptian civilizations. However, recently growing hydroponically has grown in popularity and use across many different markets.
(from Wikipedia https://en.wikipedia.org/wiki/Hydroponics)
Nutrient rich water is recirculated which allows for usually 70% to 90% efficiently on water consumption.
The vertical design allows for a higher density of plants in a much smaller footprint. With a space less than 2' diameter we are growing 42 plants with room for expansion.
The Arduino is connected to an ESP8226 which connects to your WiFi and when you create an EasyIoT account the sensors can be read through that for plant maintenance.
What are we growing?
Vertical hydroponics lends itself very well to leafy green vegetables. I am currently growing spinach, kale (dwarf curly variety), jalapeno peppers, Swiss chard, and strawberries.
Step 1: Gather Materials and Supplys;
First gather some supplies:
Arduino Mega and Uno
12V Peristaltic Pumps (2)
1/4'' vinyl tubing
1/2'' pex tubing
Cheap black pH probe
pH Up/Down Solution
5V Relay Modules for Arduino (you could also get combined ones in a shield)
ESP8266 WiFi module
Logic Level Shifter (to talk to ESP8266 through Arduino Mega)
12V Solenoid Valve (for tank fill valve)
DHT11 or DHT21 or DHT22 Humidity/Temperature Sensor
Arduino Breadboard and Various Wires
Water Level Sensor Float Switch (2)
12V Power Supplies
Hydroponic Pots (I'm using 42 - 2" pots for this)
Hydroton/ rock wool/ growing medium
4" PVC Pipe 10'
A cheap pH and PPM meter will be a great help to double check the system as well
Random bolts and fittings and some odds and ends
Basic hand tools
Heat gun (Harbor freight has them for cheap)
Drill with bits
2'' Round wood dowel or pipe (to form the net pot pockets)
3D Printer (NOT NECESSARY) I printed the caps for my pvc pipes from the Cap That Hole Customizer from thingverse , but you can just buy some pvc caps as well. Something else fun would be printing the net pots too.
Step 2: Main Growing Structure / PVC Pipe Pocket Forming
These are going to be really just general guidelines to make your own growing platform. I just happened to have that tank and the piece of aluminum so not much help there, but it could be as simple as a 5 gallon bucket and one 5' pipe section or as complicated as you can get. I'm gonna go through what i made and the controller can be applied to any size scale.
Cut the 4'' pvc pipe in half to two 5' sections, then lay them out for the cut marks. Lay out two lines long ways 4.5 to 5 inches apart. Start at 2.5 inches up on one line and 5 inches on the other from the bottom and after that put a mark every 5 inches all the way up. Using a hack saw cut on the mark just till the top of the blade is even with pvc pipe. After that heat cut area for 1 minute continually moving the heat gun on the 1500 degree mode and then shove the 2'' dowel or whatever you found in the cut to form the pocket and you can speed up cooling with cold cloth. I tried using a propane torch to heat the pipe in the beginning, but its easy to burn the pipe and is a slower process. Bolt the pvc pipes together with 1/4'' bolts to keep them together. Good link on making pvc pipe pockets and general info.
I had a weird 30 gallon bucket laying around and a piece of aluminum that fit perfect on top, so i drilled some holes to bolt the metal onto the lip of the bucket. Drill holes and mount float sensors and water intake solenoid valve, be sure to use 100% silicone as well so nothing leaks. Putting a drain valve at the bottom of the tank is also useful to drain the tank and for nutrient solution change. Remember you always want at least enough water to keep the platform stable, even with some wind. I cut out the middle of the aluminum plate and bent up the sides in order to be able to bolt the pvc pipes to the top plate with 1/4'' all thread.
Connect the 1/2'' pex tubing to the water pump, its an interference fit in my case, and at the top of the tube i inserted two 6'' lengths of the 1/4'' vinyl tubing and used 100% silicone to seal them in. Those tubes therefore go through holes i drilled at the top of the 3D printed caps (or caps from the store whichever you may choose).
In the plate i have also drilled holes to mount the peristaltic pumps for the pH correction solution. I used the rest of the 1/4'' vinyl tubing to attach to the ends of the pump barbs. I used some 1/4'' all thread with a piece of angle iron to hold the pH adjuster solution bottles to the plate.
Step 3: Wiring
DHT11 Pin = 49 //pin for DHT11
pH Probe Pin = A7; //pin for pH probe
pHPlusPin = 45; //pin for Acid pump (relay)
pHMinPin = 43; //pin for Base pump (relay)
floatLowPin = 11; //pin for lower float sensor (need a 10kOhm resistor from pin to ground)
floatHighPin = 12; //pin for upper float sensor (need a 10kOhm resistor from pin to ground)
solenoidPin = 26; //pin for Tank fill Solenoid valve (relay)
Circulation pump pin = 13 (relay)
-This was just so i could easily unplug the arduino uno and bring it inside to change pump on off intervals. As it is its 30min on and 1hr 30min off, but depending on location you may need to change that. This also could be done by using a timer relay as well or even just combining code on the mega.
You know Instructables is a great thing and all these parts have specific individualized breakdowns that can easily guide you through the process of wiring and setting up each part. You will need to use separate power sources for the Arduino and main power for the pump relays in order to not have electrical interference as well.
Step 4: Nutrients and General Info
For general nutrient reservoir info see the Wiki page. You'll want to fill your reservoir with water and let it sit for a day in the sun to get rid of the chlorine, then First balance the pH, Second add nutrients and then balance out the pH again to bring it to 6.0 This is where the cheap pocket pH and PPM meter will come in handy. This Chart is a good reference for pH and PPM levels for certain plants, it also has great info on everything hydro. As the system is now it will automatically adjust the pH but you will have to measure PPM or EC by hand and adjust accordingly. That's the total dissolved solids (nutrients) in the system and as the plants grow they will eat them up and therefore more will have to be added.
This project also has a lot of room for expansion as well. The PPM or EC can be monitored and maintained with the Arduino as well but it will have electrical interference with the pH meter so it will need to be measured in a separate container. The benefits of using a 12 volt DC power source is being able to easily adapt this to a solar powered unit all self sustained. Growing inside with lighting and air circulation (all automated) is only a step away as well, allowing for year round greens.
Now its time to get out and create. HAPPY GROWING!