hackproject.org — A Bucket a Day, a hack in agriculture — {July, 2016}

Pravin Raj Joshi
Jul 11, 2016 · 8 min read
Shailendra, all smiles, inside the polyhouse

Indira Dhungel hails from Pakarbaas. Pakarbaas is a remote village about an hours drive from the nearest river, Tamakoshi, in Ramechhap district of Nepal. It is a very dry area and there is an acute shortage of water in the village.

Indira gets water for her family by walking for about 40 minutes each trip and staying in line for 20–30 minutes each time. She does this twice a day to fulfill her daily requirement of water. There are only 2 taps that cater to about 150 households in the Pakarbaas area.

Youtube video of the original problem explained by Indira and friend

Indira’s occupation, like most others in her village, is agriculture and raising farm animals. Currently the agriculture is dependent on the rain patterns, mainly that of the monsoon. As climate change tends to become more prominent and rain becomes scarce her agriculture is dwindling down. Even the animals she raises has decreased. All around the village many patches of good agricultural land is being left fallow. Many people have even left the village to search for opportunities in other places. Indira has nowhere to go like the other 150 families in her village. Though the youngsters have left, it is the old and the women who are most around the village.

Indira is dependent on her farms to grow her vegetables and other crops. Since water is so scarce this is proving to be more and more difficult.

Before starting we set out the parameters within which we will need to work so that we could replicate our efforts into tangible solution for Indira at her village in Pakarbaas, if our solution went anywhere.

It had be to extremely affordable — we set limit at USD 100.
It had to be made with local material as much as possible, yet had to be reliable and durable.
Fertilizers are costly. So compost or local fertilizers had to be given priority.
The most important one — it should be possible to irrigate with the least amount of water — our initial target was 1 bucket (20 litres) a day.

We chose a piece of land that had too many small rock and stones in the soil, where most people had given it up as being unproductive enough not to work on it. We thought that could be a good start to try and replicate some of the land around Pakarbaas area. We got the polyhouse built with the help of some people who had made one before. It is 10ftx2.5ft. The plastic we got was the thinner variety in an effort to see if it would work to reduce cost.

Preparing and building the polyhouse

Out of the numerous whimsical projects that we had worked on in the past one was to try and produce bio charcoal out of sugarcane residue. Though it had worked only to a certain level, we had been convinced by the productivity of bio charcoal. So we thought, if nothing else we would add bio charcoal and that is what we did. We mixed a generous helping of bio charcoal in the soil while preparing it for seeding. We added no other fertilizer as we could not find consensus among people giving us advice as to what would be good.

We studied through articles on the Internet on various types of irrigation schemes and settled down on drip irrigation. That was the first scheme we wanted to try, but we had many more to try in mind. We laid down thin pvc pipes on the soil.
Got the water tank and ran water through the line. It worked as we expected.

We had multiple discussions with multiple individuals and organizations, all either involved in or known as experts in agriculture to get all their viewpoint. We talked about soil, environment, water, types of plants and just about everything under the sun. Half way towards all these conversations we realized that we had forgotten the basic principles that we were taught as children — photosynthesis. However the ideas were presented it all boiled down to try and make sure photosynthesis is done right to optimize plant growth.

Through multiple studies and discussion, out of the various parameters, we found that the parameters we most needed to work with are sunlight, temperature, humidity, water and carbon dioxide — parameters important to photosynthesis. There are other parameters to look at like quality of seeds, fertilizers and the chemical contents of them, trace chemicals that are required by certain plants, etc., but we needed to focus on some core parameters first and then look at others.

We built a raspberry pi based sensor kit to monitor temperature, humidity, soil moisture level and carbon dioxide and ran it inside the polyhouse at all times to measure the levels of each. Though we removed the kit after about 1 month of operation and found that we really don’t need to constantly monitor as the parameters tend to stabilize inside the polyhouse.

We got the paddy ready for planting seeds, but slowly realized that the small rocks and stones started to show up as and when we started running the water. This sent us back to watering. We looked for various solutions and an expert pointed us in a direction that we have followed so far.

One of the compost making bins, initial growth and Shailendra prepares the pipes for drip irrigation

Water is normally required between 10cm to 25cm underneath the soil. This is the root area and from where water is mostly taken by the roots. It does not matter whether water is there on the surface. We realized that drip irrigation was good, but kept water at the surface a lot. So we were suggested to try flood irrigation. Testing with this now we have concluded that we really don’t need a bucket a day. All we need is about 20 liters of water every 5 days to flood irrigate the polyhouse. This we normally do in the evening, so that evaporation due to heat is reduced throughout the night and water gets to seep into the soil.

Temperature and humidity seems to be taken care for by the polyhouse, this we found out from experts, from online texts as well as from our own raspberry pi sensor kit readings.

Seeds we decided to buy only local seeds that we could find on the street markets, mainly sold by other farmers. The reason for this is mainly to think from Indira’s point of view that she might have access to only these kind of seeds.

Fertilizer we looked around a lot and finally settled on something that we had had all along — compost made by Kale Thami as talked about in this medium article. This had proved to be very good so far.

The remaining portion was carbon dioxide. We found the average content in the air in Kathmandu is about 330ppm. As an expert had advised us and from content we had seen online it would be good to raise the carbon dioxide to over 450ppm. This is a problem we could not find a reasonably cheap or replicable solution to.

We have multiple crops from the polyhouse in the last 2 months, mainly of micro-greens. We also have had a good harvest of coriander, amaranth and other greens. Recently we have planted tomatoes and chillis. There is also a small pad of beans growing, but it hasn’t cropped yet.

All greens inside the polyhouse

Summary of our learning:

  • Polyhouse needs better quality plastic casing.
  • Bio charcoal is great. Mix with compost and use and it becomes better.
  • Flood irrigation is great. So no need for “a bucket a day”.
  • Well digested compost works wonders, but finding digestion level is hard.
  • We really could not figure out how to inject carbon dioxide into our polyhouse.
  • We can grow pretty rapidly, specially greens, that would be good to use in homes.

What we felt we could do better if we could learn a little more:

  • Understand scientifically what worked and what did not work with proper explanation to our experiments. For us it feels it has worked as we are getting crops and it is nice, but some knowledge base as to how it worked would be really helpful, as a matter for replication.
  • Some way to capture and inject carbon dioxide into the polyhouse.
  • More about fertilizers that can be produced either inside or alongside the polyhouse.
  • More variety of vegetables that can grow very quickly.
  • to improve upon what we have or to radically change for a better design while still keeping the cost very low and the polyhouse very usable

“Can we improve upon what we have or can we radically change for a better design while still keeping the cost very low and the polyhouse very usable?”

  • Create a cheap fit it yourself polyhouse product that is pre-designed for flood irrigation.
  • Generate compost in liquid form to use along with the flooding.
  • Monitoring kit that will sense and inform the major parameters for this type of polyhouse.
  • Our focus from time to time has been the carbon dioxide. Nearby our polyhouse is a kitchen that serves over 1500 lunches per day. They cook on big fire and we see a lot of smoke. It would be nice if we could somehow get the carbon dioxide from there and pump it into the polyhouse. This could be replicated all around as most villages still use open fire for cooking as well as for making ash and food for animals.

We would really love to improve on this and create a kit that is affordable, yet extremely usable for Indira and people like her around the world. We would like to learn more about what we could do, not only to make this better, but also to see options that would be good for Indira.

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