The RoboGarden or, “Do Android Cukes Dream of Electric Salads?”

Garden Brain
This is Carver, the brain.

I’ve been so busy DOING this project that keeping updates here has eluded me. I had previously written about the Food Computer concept being deployed by the MIT Media Labs Open Agriculture Initiative. I was keeping an eye on the progress over there, intending to build one of their systems. I decided to temporarily “do my own thing” for a couple of reasons. For starters, their system is in development, and jumping in now requires a level of knowledge that escapes me. I’m just not up to speed on the level of software development required to use their approach right now. Second, I have decided that building my own setup based on a traditional hydroponic system has more value and efficiency for me at this juncture. I eventually hope to have a system that is 100% compliant with the MIT approach, so I can contribute to the data gathering, educational, and community based initiatives they are so gallantly spearheading.

So, why go your own route? 

As I mentioned, my software development abilities drift far behind my hardware abilities. I am a bit lost looking upon the sea of code that MIT has out there. I have already put a number of the pieces together in preparation, but I knew my own approach would be a less frustrating way to actually get results. Reason number two is cost. By some estimates, the food computers can quickly run between $2,000 and $3,000 (depending on who you talk to and what materials you source). I have a currently running system that has cost me $1000 to date, and is just about to produce food. A third reason is the systems footprint. My system has about 4 times the grow area of a standard food computer (in fact, my system is almost better described as a “food server” in some regards). This means I can grow an actual useable crop. The standard food computer is a great opportunity to experiment, but the actual output would be pretty low as far as trying to feed myself. And thats my fourth reason, feeding myself. I have a lofty goal that someday I will grow 100% of my own food, so this is a step toward that goal (especially in the winter). I don’t eat meat, so veggies are the only thing I need to produce. Those of you that follow this blog will say “Hey, didn’t you write about eating the squirrels that plagued your camper?“, and you’d be right! Well, that was then, this is now, get over it (smiley face). Of course, going my own way has some disadvantages.

What are these disadvantages of which you speak?

Well, many of the problems have yet to surface, I’m sure. I’m on my first crop, so I have no idea what the final results will be. Will I get fruit at all? Will it taste like cat food? Who knows. A big problem is that my system is just one large system with one climate, one light cycle, and one nutrient spread. I have to be cautious what array of seeds I plant. If they require different nutrients or lighting,  or have vastly different timing of growth stages, or different tolerances of heat, humidity and pH, it just won’t work. My idea of a constantly rotating crop (eating one crop while starting a new one) is likely to be impossible. I may have to do one crop, can/freeze/preserve it, and move to the next. Perhaps I will reserve its use to crops that cannot grow in my difficult climate, and stick to soil for others. It’s a lot of question marks that will only be answered with time and results.

The most important disadvantage is that my system limits the data and knowledge I can contribute back to the MIT project, which is open source. Wanting to support their open source initiative is my motivation to push myself to build a proper food computer ASAP.

Blynk App
Remote monitor and control courtesy of the Blynk App

Cool story, just tell us about your setup already.

So it’s built with the Particle’s Photon microcontroller. It uses a temperature/humidity sensor (an AM2315), and a simple LDR to sense light levels. There is a propane furnace keeping it warm in our sub-zero temperatures. The brain (pictured above) uses a bank of relays to control two dual gang outlet boxes. The left 4 outlets are individually switchable, while the right are switched in pairs. This controls all of the pumps and lights and fans.

My code tells everything when to turn on and off. It can be overridden and manually controlled using an app called Blynk that talks to the system remotely and also allows me to monitor from afar. It texts me when the temperature drops low, alerting me to change the propane tank. That’s all setup using IFTTT.

In terms of hydroponic style, it’s a flood and drain system. The pump runs long enough to fill my tray, which then drains back to the holding tank. This keeps the roots wet and oxygenated. The water has a nutrient solution balanced for the needs of the plants. The water is oxygenated with a pump, much like a fish tank is. The pH is controlled via application of acids/bases depending on careful readings from a meter. I’m using a Hannah 98129 Combo meter that tests pH, Conductivity (EC), and Total Dissolved Solids (TDS). My grow light is an 8 tube, 40,000 lumen, T5 fluorescent unit by Agrobrite.

Operation Transplant

I started seeds on 1/20/17. By 1/31/17, I had seedlings ready to transplant. The seeds were started in rockwool cubes. The seedlings (cube and all) were then transplanted into net pots filled with an inert clay substrate. Every hour, the tray floods and drains. The light initially stayed on for 18 hours a day. Today, that changed to 12 hours a day. This is interpreted by the plants as the days getting shorter. It’s their cue to start flowering and producing fruit.

growth progress
Salad O’clock?

When my cucumbers began to reach out vines, I set dowels out to catch them, but today I switched that to a net trellis. I also switched my nutrients to a flower/bloom friendly variety. As you can see by the picture, I have come a long way from seedlings.

As always, anyone who would like to build something like this is welcome to my code, which I will probably place on GitHub at some point. Just email me from the contact page. I’ll write more when I start seeing fruit.

Nerdfarmers unite!


My First Garden

Nothing to see here.

The idea of growing a garden had crossed my mind on and off for a quite few years. It was always something I would “get around to” someday. It was always, “maybe next year”. This year, I finally took the plunge. I didn’t get started until late in the season. It was almost the end of July when I finally got my seeds in the ground. I figured I would just get what I could out of it. Even with total failure, at least the hard work of prepping the land would be done for next year.

My late start ended up being a bit of a blessing. We got an impressive amount of rain early in the summer, and a lot of my friends lost their early plants as a result of drowning in puddles or being washed away. I picked a spot near the camper, but far enough away to avoid the shade of some tall spruce trees. My crop selection was as follows; corn, carrots, beans, romaine lettuce, basil, and cucumber. I decided it was too late to attempt tomatoes or peppers.

I thought about just tilling the grass into the soil, but decided I would have a cleaner, less weed riddled plot if I removed the sod. This was a back breaking process. You may notice a tractor in the background of the pictures, but this is not my tractor. It belongs to my aunt next door, and I certainly could have used it, but I guess I wanted the whole “frontier living” experience. At one point, my dad drove by on the tractor while I was lifting sod. “You know we have a tractor?”, he asked, as though it had slipped my mind. “Well, I have a shovel.” I answered. I felt like I might never get all that sod out, and I had to stop for a week when my back had had more than enough. I let him try to help with the tractor, but the attempt to lift the sod with the forks was making more of a mess than helping. This is not a farm tractor, and they own no farming attachments. So, back to lifting it out one square at a time.

Tilled and waiting for seeds.

Eventually, I was ready to move on, and my neighbor, Dale, came over with his tiller. I fixed his recoil in exchange for use of the machine. I had let the sod chunks dry out so I could shake the usable soil from them before carting them away to compost. I even sifted out an impressive rocks, crawling on my hands and knees with a screen. I figured this was worth doing right, as failure meant waiting until next year to try again. The planting was a fast and simple process, though the carrot seeds were so tiny and difficult to handle that I worried they were planted too dense.

And then there was food.

Next was the waiting game. I have worked on my patience a lot, and this was proof that the work has paid off. But once I started to see life, it took off quickly. It was an impressive display of earths majesty to watch this unfold. The amount of growth from one day to the next was impressive. On days that I pulled out weeds and churned the earth a bit, the growth was just astonishing!

It wasn’t long before I was enjoying lettuce, with cucumbers shortly thereafter. The basil took quite a while to show up, and it was a small leaf variety that was difficult to work with in cooking. Eventually, the carrots were getting to an edible size, and I was impressed that the overcrowding wasn’t more of a problem. I’m sure they would have done better spaced out more, but I had a high percentage of good size carrots that grew deep into the soil. The beans were struggling, with no signs of flowering, and the few corn seed that took were having trouble standing in the winds I was getting. I’m pretty sure crows go to some of the corn seeds.

I did some pest control. We had a family of ground hogs next door, and raccoons are common. I set out a large live trap, eventually catching both groundhog parents and the child. All of them were driven away and reunited elsewhere. I got one raccoon as well.

I learned a lesson about beans. There are pole beans, and bush beans, and I did not know there was a difference. I figured the pole was a personal choice, allowing you to grow vertically and therefore tighter, much like a trellis for cucumbers. I eventually came to this realization, and installed poles. At the end of the season, the beans had climbed the poles and started to produce beans, but it was a bit too late.

What’s up, Doc?

So the beans were a wash, the basil was not a good variety for my purpose, the corn didn’t have enough time to grow, and only half of my cucumbers took. But, the cucumbers that took were EXCELLENT! The lettuce was a huge success, I was eating lettuce for weeks, even after a few frosts.

16lbs in total.

The true triumph was the carrots! I was picking a few here and there as they were ready. I brought quite a few into work to share with coworkers. Finally, at the end of the season, I pulled the rest up. The last harvest was 16 pounds worth. I canned 8 pounds. I would have done more, but I ran out of mason jars, as did the grocery store. The remaining 8 pounds I ate and shared. They lasted for weeks in the the fridge. And now I have jars of carrots that could last me for most of the winter, though I plan on giving many out for Christmas.

My own grocery store.

Now that there’s about 3 feet of snow on the ground, I’m shifting my attention to a new endeavor – an indoor hydroponic operation, that will eventually include a food computer. What is a food computer? Well, you’ll have to keep coming back here to find out…

Enter, The Food Computer


openaglogowhite_small2The coolest part of my trip to the White House was the discovery of the Food Computer. This device is the small scale prototype for a much larger project taking place a the MIT Media Lab. It’s the work of Caleb Harper who is behind MIT’s Open Agriculture Initiative. The project has several aims. Ranging from educating kids about food (where it comes from, how it grows, etc…), researching how to grow better food, and of course, feeding people.


Caleb’s PFC hardware guts

Enter, the Food Computer

The PFC (Personal Food Computer) is the open source hardware and software system being developed to help change our food future. In layman’s terms, it is a system that controls all aspects of the plants environment over its whole lifespan. Since different plants have different requirements, the system uses a “climate recipe” (which is simply a series of instruction for the computer) designed the plant in question. Basically, you plant a seed (or a started seedling), select the climate recipe, and press play. The machine will maintain the right temperature and humidity, it will provide the proper nutrients, it will cycle the lighting, it will do everything the plant needs. Then you eat it.

My Raspberry Pi and Arduino getting set up for growing.

How does it work?

So, as you might expect, it’s a bit more complicated. There is quite a lot going on under the hood. Here’s bit of geek-speak; It uses a Raspberry Pi as it’s brain, and an Ardunio Mega for the heavy lifting. The Arduino controls the mechanical bits like pumps, and relays, and monitors the array of sensors. The sensor data is passed to the Pi where the climate recipe can tell the Arduino when to perform necessary functions. For example, a pH sensor tells the system when to raise or lower the pH, and a peristaltic pump can supply a solution to make that change. It also does this with the nutrient solutions electro-conductivity, among other things. You can control CO2, Dissolved Oxygen, and nutrient solution temperature. So, the pant receives everything it needs, precisely when it needs it, (ideally) without human intervention.

Caleb’s PFC at SXSL growing basil

As we speak (December 2016), the PFC V.2.0 is being released. The original version was more difficult and expensive to build. V2.0 is working to change that. It’s an alpha release right now, so there is still work to be done to make it as cheap/easy/accessible as possible. Being open source, anybody can download the plans and the software to build one. You can contribute your ideas to make it better. The release of the plans is an ongoing process, so don’t expect a simple plug and play approach just yet.

So where is this headed?

As the PFC becomes more accessible, more people will build them (including schools, some are already doing so). The plan is to make kits available for purchase to simplify the part sourcing. As the user base increases, a database of climate recipes will amass. You can download a recipe that suits your needs, or you can experiment and upload your own results for others to use.

Whats really exciting is the opportunity for knowledge. Caleb described to me how his team freeze dries the resulting plants and places them in a spectrometer to see the nutrient/chemical break down. They can change growing variables and see the direct results of those variables on the plants chemistry. They can stress the plant in very specific ways (light or nutrient starvation, bacteria introduction, pH/EC shifts) to see what chemical defenses it puts up, and how that changes the nutrient/chemical properties. These things affect the flavor, the nutrition, the shelf life, etc… The best part is, IT’S ALL REPEATABLE. A good result can be downloaded and recreated by anyone, anywhere, with a PFC.

Food Servers and Beyond

The PFC is admittedly small. You aren’t going to feed your family with it. It’s footprint is about 3 feet wide by a foot and a half deep, and it stands maybe 3 feet tall. It could fit on a counter or a small table, and can grow about 4 small plants at a time. But the PFC is simply the home version of what MIT is really building at OpenAg. The PFC is like a test platform to get us geeks involved and improve the system. The lessons learned in the small scale are being put to use in Food Servers. The servers are built in shipping containers, using the same hardware and software. This is all happening now, in the new lab that OpenAg has just opened. The next phase is the Food Datacenter, which scales the project to warehouse size. The scalability is built into the project, so it’s instantly scalable without having to be reimagined.

Servers and Datacenters can be deployed in various ways. They have a home in climates that don’t support standard agriculture, they have a home where food is scarce and people are hungry. In America, they have a home in the city. According to the census bureau (in early 2015), 62.7% of our population lived in the city, and cities make up 3.5% of our land. The food to feed our population often travels an enormous distance. The urban agriculture push seeks to change that. We see more city gardens and roof gardens, but it’s not enough. There is talk of entire floors of skyscrapers becoming farms. This is where food computers can play a role.

So what is my plan?

I am WAY into the whole food computer concept, and I hope to contribute to the initiative ASAP, but I am financially challenged. They are working hard to make a system that is affordable to build, but obviously this system will presumably lack some of the higher tech solutions that MIT is deploying in their own systems. I’m keeping my eye on their progress, and buying what I can, when I can, in order to deploy a PFC. But I’m not spending my time idly, I’m building my own hydroponic system.

Armed with a prime directive of feeding myself, the PFC is taking a necessarily secondary position, but I’m keeping it’s spirit nearby. The systems I’m designing to control my growing environment are taking their cues from the PFC. I’m trying to keep my equipment selection to PFC compatible options. Eventually, I hope my system will run on the food computer software. In that sense, I’m skipping the PFC and going straight to the food server, though I do plan on having a dedicated PFC as well.

I already have about 80% of my hydroponic operation setup, and hope to be starting seeds by the end of the year. Naturally, I will be writing about the journey as it unfolds.

Keep making stuff (and remember, growing food counts as making stuff!)