The DIY Smart Garden System

I’m going to take you on a tour of Do It Yourself Smart Gardening

My name is Cory, I’m a Technical Craftsman specializing in creative problem solving within electronics and software engineering.  Professionally, I’ve worked as an electronics engineer, a plastics fabricator, software engineer, an industrial laser technician, and, of course, a coffee barista.  I’ve spent the last several years working on a Smart Garden System project I named, hydroMazing.  I’m sharing my work with you because I would like to empower everyone who is interested in a “Smart” approach to gardening.

What we’ve covered so far:cropped-hydromazing_smart_garden_system

 

Are you interested in following me on this journey?

Now that we have an understanding of what it takes to provide an optimum indoor growing environment we can start analyzing the cost-benefit of further optimizing and automating the system.  Please share with friends and follow to receive a notification when I publish the next section.

Section 1:  Let’s start by using an Arduino Nano on an Expansion Board to monitor the indoor gardening environment.  We will measure light intensity, ambient temperature, relative humidity, nutrient/water temperature.

Section 2:  Continue working with the Arduino Nano on an Expansion Board to control appliances in the indoor gardening environment.  We can continue working directly wired or we can start working with wireless communications.  Wired or Wireless?

Section 3:  Add an Arduino Uno using an LCD with Buttons Shield to provide a display and alerts.

Section 4:  Add the Raspberry Pi for remote access, notifications, data collection, and analytics.

Section 5:  More sensors:  moisture probe, pH, E.C., carbon dioxide level, flow-rate, liquid, float (liquid level switch).Peristaltic Pump

Advanced:  Using Dosing/Peristaltic Pumps for Nutrient Solution Management.

Using a Raspberry Pi and USB Camera  Use Raspberry Pi to monitor or collect snapshots of the garden using a USB webcam.

Do It Yourself:  hydroMazing Smart Garden System Kit

Kit includes wired and ready sensors and components for making the Controller Module (Arduino Nano) and Web Services Module (Raspberry Pi)?  Let me know, Contact Cory

Please share with friends and follow to receive a notification when I publish the next section.

Managing Nutrient Solution Systems

A nutrient solution system typically consists of a two or three part liquid solution containing the essential diet for a plan added to clean tap water.  The manufacturer of the nutrient solution will include or reference a feeding schedule recommended for various common types of plants. Unfortunately, most minerals are mined and processed by the manufacturers, however, many offer an organic option while some specialize in only organic.

f6tq65zid7v1e0g-medium
nutrient starter kit

I recommend starting with General Hydroponics Flora Series Performance Pack, consisting of the main three liquid parts, several enhancements, and the pH test kit.  There is also an organic line of products. (Handy tip: If you ask General Hydroponics or other nutrient solution vendors for samples of their products, you can usually get free or discounted trial sizes.) A word of caution about miracle growing fertilizers, do not add any fertilizers other than those you know to be hydro-friendly, as it can cause a nutrient build-up harming your plants.

Making Your Own Nutrient Solutions

There are several challenges involved in making your own nutrient solution.  Sourcing the raw minerals needed, breaking-down properly so that the plants are able to absorb the nutrients, and filtering out unwanted materials that will clog the flow of nutrient solution through the system while maintaining a proper pH and hoping that you didn’t inadvertently introduce an undesirable pest into a closed-system.

Experiment with microfungals:  Make your own hydroponic compost tea

Nutrient Solution Management

image01

The most common vessel for transporting and storing water is the 5-gallon plastic bucket, also commonly available in 3-gallon as well.  The most common method for managing liquid is to use ½” diameter vinyl tubing and fittings.

If we do not monitor the nutrient solution concentration and the pH then the plants will reach a point where they will show signs of stress.

What is EC?

The electrical conductivity (EC) of water estimates the total amount of solids dissolved in water -TDS, (Total Dissolved Solids). TDS is often measured in ppm (parts per million). In hydroponics, this measurement is used to determine the approximate concentration of nutrient solution to water.

As the nutrient solution level decreases it needs to be replenished with freshwater, otherwise the nutrient solution becomes more concentrated and some plants won’t respond well. Add fresh water to bring the concentration back to the level it was when started, often referred to as “topping-off.”

What is pH?

The pH of water is an important measurement whether you are gardening indoors or outdoors, soil or soilless, because it affects whether a plant can properly take in nutrients.

Check the pH and EC periodically and compare it to what is expected for that plant at this stage of growth.  There is no need to adjust your pH or EC until it is necessary. There is a lot of misinformation out there about keeping the pH and EC regulated. If I were paranoid, I’d say it was a conspiracy from hydroponics manufacturers and retailers who want to sell more consumable product. Don’t get me wrong, proper pH and EC is important, even critical, to the success of a plant.  There are many hand-held EC devices available as well and if you are checking the E.C., it’s a great time to check the pH.  Therefore, I recommend a handheld pH tester such as the Oakton EcoTestr pH 2 Waterproof pH Tester, which is excellent for the home gardener and has been proven time and again to be accurate.

When do I need to adjust the pH?

Only under the following conditions:  pH is at or below 5.0 or above 6.5

AFTER at least 30 minutes from the time of topping-off or changing the nutrient solution.  I recommend using a solution made specifically for this purpose, pH Up and pH Down from General Hydroponics sparingly and only when necessary.

Flushing

Flushing means to literally flush empty the nutrient solution from the hydroponics system and replace it with fresh “good” tap-water. Then return the nutrient solution back to what it should be for the phase of growth. When in doubt, flush the system and refresh the nutrients. Otherwise, it’s recommended to flush your recirculating system every 7 – 14 days. When I grow, I try to keep the nutrient solution working as long as possible, however, salts build-up over time and it is good to flush with fresh water from time to time.

 

More Info:

Please share with friends and follow to receive a notification when I publish a new article.

What is hydroMazing Smart Garden?

Control

The hydroMazing controller is designed to operate ventilation fans for air circulation, water pumps, occasionally a humidifier, heaters, or any other appliance that is necessary to maintain an ideal environment for plants to grow.  Typically, we DIY’ers would hook-up some relays to a microcontroller to achieve control.  However, with hydroMazing, the system uses remote controlled wireless AC outlets, ensuring safer control than traditional relays.  hydroMazing uses low-cost open-hardware modules and the ubiquitous microcontroller, the Atmega328, on an Arduino Nano*, offering the flexibility of customization and expansion. The sensor choices are endless, but I’ve narrowed it down to a few important and relatively inexpensive modules.  A temperature and relative-humidity sensor, moisture sensors for soil, liquid temperature probe for hydroponics, a simple photocell.  There are many other optional additions including the float switch or switches and flow-rate sensors.

The wirelessly controlled outlets proved to be a etekcity_outletsreliable method of controlling the fans using the Arduino to send the signals depending on the temperature sensor’s readings.  It didn’t take long for the source-code to evolve into a beast.  The Arduino family of microcontrollers is limited in how many instructions it can run and hitting the program size limit doesn’t take very long when you want to control more than a few blinking LEDs.  I have found that the size limitation has forced me to write better, more efficient code than I initially do.  Even with creative variable handling and custom libraries, eventually, there is a need for another microcontroller or to move to a larger one.

Wireless Monitoring w/o Internet

There are several ways that the microcontrollers can communicate with each other.  The least expensive wireless method I could find is the nRF24L01 wireless radio transceiver. The module is a low-power, lightweight variety of bluetooth giving hydroMazing the ability to communicate with a monitoring unit.fpzexmwi7vqs7mr-medium

I decided to add another Arduino Uno with an Liquid Crystal Display shield so that I could display what the sensors were reading, the state of appliances, and alerts with notifications.

frv8uq9i800wgat-medium

mmexport1472732631987

I made my own open and adaptable platform that can be custom tailored to a wide variety of gardening needs and conditions; yet, also a self-contained wireless system.  The open-architecture of the system allows for ease of integrating Internet connectivity and web services.

Internet Monitoring

Enter the Raspberry Pi connected with an nRF24L01 module.

I was able to modify much of  my Arduino Source code to listen for incoming transmissions and then write that data out to a few files.  First, a log file that captures all communications between the Pi and the hydroMazing Monitor.  Next, I have the program write out the current state of all sensor objects and a file for all of the appliance objects.  When an alert occurs the progrhydromazing-liveam will create a file containing that alert.

I then added a PHP script to read in the data object’s from their respective files and display live on the Pi’s Apache server.

hydromazing-alert

Next, I wrote a Python script to read the directory for the alerts file and if it exists, read the file, parse out the pertinent information and then email or through SMS text the user.  In addition to sending an email or text alert, the python script moves the alert file into position for the PHP script to read and display.

Using the log files that are created, I am able to import the data into a database.  Once the hydroMazing’s data is recorded into a database residing on the Raspberry Pi we can start performing analytics and generate some reports.

Monitoring and controlling the system is mostly done for us, but when the hydroMazing needs to alert us to a problem it can now by using the Raspberry Pi.

 

img_20161001_145206012

With the hydroMazing smart gardening system, you can grow healthy, happy plants anywhere!

Contact us today for more information!