Growing
Smart
This article is part of Issue #5
Where the Leaves Fall talks to John Francis Serwanga, the hydroponics expert at World Food Programme (WFP). John Francis has over 17 years of experience with hydroponics projects, including as hydroponics consultant with WFP Namibia and Zambia. He is currently working with Zambian schools, as part of WFP’s H2Grow programme, to show teachers and pupils how to use hydroponics to grow vegetables to supplement the government’s homegrown school feeding programme.
Where The Leaves Fall: What is hydroponics?
John Francis Serwanga: Hydroponics is a method of growing plants without soil in a nutrient water solution. It is a climate-smart and cost-efficient solution, using up to 90% less water and 75% less space than traditional methods, while producing crops at faster growth rates.
The method has got a lot of advantages. Because the nutrients are readily available in the water solution, the plants can be planted closer together and they grow fast because there is no competition for nutrients as there is in the earth. For example, here in Zambia, we can plant vegetables and three weeks later we are harvesting.
When I was growing up, I tended to hate agriculture because of the heavy work. Hydroponics has a good advantage over that: it’s smart, there’s no digging and no weeding. It is less labor-intensive in terms of money and time. It reduces the risks of pests, most especially the pests found in the ground, because you are not planting in the ground.
Hydroponics also allows for more controlled and effective use of fertilisers: you are able to measure the exact quantity needed by the plants at all growth stages. The planting is done in a greenhouse, which also gives you control over temperature, humidity, and all the climate conditions.
WTLF: What is the H2Grow programme?
JFS: H2Grow helps vulnerable communities build their own hydroponics systems so that they can grow food anywhere and any time. Through collaboration with H2Grow innovators, we have been able to break hi-tech hydroponics into sustainable, affordable and adaptable systems that can be powered manually, with solar, and with rechargeable batteries.
It can be practiced any time of the year, in any given environment. We have tried to simplify hydroponics using local materials so that it’s easily adaptable to any environment, without any limitations of space or climate conditions.
Hydroponics is a life-changer, particularly for developing countries, because you can literally use anything.
WTLF: What do you need to set up?
JFS: Hydroponics is a life-changer, particularly for developing countries, because you can literally use
anything. The plants are growing in the water, and this water has the appropriate nutrients. We use commercial hydroponic fertilisers, and although this is not always readily available, we are developing locally available solutions.
Here in Zambia, we are using cement bricks and plastics to build our water reservoirs. At one point we used palettes, we have used timber, and in other areas we just dig in the ground, lay down plastic and make a reservoir.
Often, when people come to us for training, they have a water bottle for drinking. After that we cut off the top and use the top as our net pot to hold our plants. We’ve also seen cases of people using eggshells, and they’ve planted seedlings in the eggshells. Communities have demonstrated an open mind to this technology and are adapting to local materials, which is good for the future of hydroponics in Zambia.
WTLF: Is there a limit to what you can grow with hydroponics systems?
JFS: It depends on your expertise and knowledge. If you fully understand the concept it becomes easier to play around with the system to accommodate different plant types.
Where have the systems been applied so far?
The H2Grow programme has been set up in nine countries so far. Here in Zambia, the places where we are setting up hydroponics are usually drought-prone areas where they struggle to harvest, but the systems are working well.
Namibia is found in the middle of the Kalahari Desert, where soils are sandy, but we have been able to successfully implement hydroponics. We started with one greenhouse funded by the United Nations Office on Drugs and Crime at Gobabis Correctional Facility. The aim of the project was to rehabilitate the prisoners so after their sentencing they can have some skills to use outside so that they don’t commit the same crime. Now the prison is supplying fresh vegetables to supermarkets and they have since added three more greenhouses. And many of the offenders are go-ing back out into society and they are setting up hydroponics systems when released.
In Algeria, we are growing in a desert and the hydroponics is doing very well. Libya recently joined the H2Grow family and will be growing animal feed using upcycled materials like jerry cans. In Sudan operations have been put on hold due to conflict, but we hope they can be continued in the future, and we have also shared our knowledge with an NGO partner in North Darfur where they have started growing vegetables in circular gardens.
Many private companies have realised the potential of hydroponics and started stocking many of the inputs from South Africa.
WTLF: Can you tell us about your current schools project in Zambia?
JFS: The Zambian government through the Ministry of General Education is implementing the homegrown school meal programme, where students are given a meal during school time. The food basket is limited and mostly consists of cereals and pulses.
Recognising the need for diet diversity, the government recently prioritised the establishment of school gardens to enable schools to supplement school meals with vegetables and promote nutrition education.
However, climate change is affecting seasonal patterns and most schools face significant climate-related challenges. Zambia experienced two consecutive droughts in the 2018-19 and 2019-20 agricultural seasons. In the 2018-19 season, an estimated 2.3 million people faced severe food insecurity.
Then there are pests, which are coming during the rainy season, like locusts and armyworms. When it starts raining most farmers are affected by pests and plant diseases and can lose their entire production due to this. So global warming and climate change has really affected agriculture production. It’s a challenge.
This means that the school gardens cannot produce all the time. They only have one rainy season in a year. When the rainy season is finished the garden harvest becomes very limited and sometimes non-existent, but schools still need to provide nutritious meals to their students. That’s why we came to close that gap, the production and nutrition gap, with sustainable approaches to ensure that schools grow vegetables year-round to supplement the meals served to students.
Our project has established 23 school sites across the country, each one with a greenhouse containing around 2,000 plants with current monthly production averaging at 1,272kg per site. The introduction of hydroponics has helped the schools to provide those fresh vegetables to students. We are growing spinach, lettuce, Chinese cabbage, kale, and amaranth, while also promoting skills and knowledge transfer.
The system also allows for income generation to sustain the project. For instance, because of Covid-19 induced school closures, students have not been going to schools, so schools like Bulungu Primary School in Mumbwa district have been supplying supermarkets with fresh lettuce as a source of income to buy fertilisers. We are trying to work out a programme that links other schools to the potential markets such that during the school holidays they can still produce and sell to the supermarkets.
WTLF: Is there a particular hydroponics method you are using in Zambia?
JFS: There are a number of different hydroponics systems, but the one that we have been implementing in Zambia is what we call deep water culture. You get a basin or bucket, fill it with water, and make sure the plants are floating on top. You don’t need to change the water, just top it up when it gets low.
The reason why we have been implementing that system is because of its simplicity for beginners. There is less tech, you don’t need power all the time to pump water up and down, and it can easily accommodate vegetable horticulture plants. So deep water culture is a lot easier to bring to a beginner. It’s a bit hi-tech, but it’s doable.
Another type of hydroponics system we use involves pumping the plant mineral nutrient water through tubes and cycles. This is best used for certain plants like tomatoes and peppers plants.
At schools where the facilities are good, we have set up both systems. At schools in rural areas, where the facilities are not reliable, we have resorted to the grain bag planting system, which is not a hydroponics system. It’s another controlled form of cultivation with soil in a grain bag. Before we use the soil, we treat it to kill whatever germs the soils could be having and then amend it with biochar (charcoal dust) and organic fertiliser. Charcoal dust is everywhere here in Zambia because is the main source of energy for cooking. Biochar’s advantage is that it maintains the soil pH and retains water.
Bags are placed on a plastic surface that means the grass can’t get into the bag and whatever is on the ground does not have access to the bag. The bags are placed in greenhouses so they do not dry out. The watering in the bag is minimal, perhaps twice a week. In this system, we are able to plant anything, including tubers like carrots, fruit, and other heavy plants like eggplants. The time for maturity is comparable to hydroponics, and it’s also smart agriculture.
Products are very nice, they are very healthy, and it requires less technical expertise than hydroponics. So, we’ve been implementing both systems in schools.
WTLF: What did you source locally for the project?
JFS: When we started the pilot in September 2019 it was very challenging. Hydroponic fertiliser, air pumps and other accessories were not locally available in the country: water had to be pumped by hand. But with the involvement of the private sector and local artisans, more solutions and alternatives are now being suggested in the project implementation stages.
Many private companies have realised the potential of hydroponics and started stocking many of the inputs from South Africa. Also, good, innovative ideas are being implemented by students: at Edgar Chagwa Lungu Technical school in Petauke they are developing a manual air pump.
Tell us about the condition of the soil in the school gardens?
The condition of the soil generally in Zambia depends on the region. We have very sandy regions, particularly on the western side of the country. In the sandy soil, the fertile levels are very low, so on that side of the country, it is very hard for the schools to produce. However, during the rainy season, even the sandy soil can produce, though the output will not be that good.
In other areas, you find that the soil clay content is too high. Production becomes a challenge. In the north, they have some good soil. But even there they face big challenges, ranging from infertile soils to poor water retention. As a result, farmers are forced to use fertilisers, which are expensive, for every planting season. So, for a school garden to produce, you find that the cost of production is very high, because they need to boost their soil almost every time.
WTLF: How is the availability of seeds?
JFS: Seeds are readily available and there are many companies that are selling them, but you have to buy them every season. Seed and chemical companies are very big in Zambia, and make a lot of money. In some areas, where farmers cannot afford these seeds, they turn to use recycled seeds, which are not as productive as the modified varieties.
What is the water situation?
Access to water is a challenge in some parts of Zambia. For instance, the western and southern provinces face significant water-related challenges and these areas are mostly prone to droughts. However, after the rainy season, there is underground water that can be captured by digging wells or boreholes. However, not all communities can afford this. This is were hydroponics can play a significant role in reducing pressure on water access while maintaining productivity.
There are other options to improve on-water access, such as rainwater harvesting, which is something that we are looking into.
WTLF: How have you engaged teachers with the programme?
JFS: Agriculture forms a significant part of Zambia’s economy, though with heavy reliance on traditional practices. With the introduction of smart practices, people are interested to find out more. School administrators are cooperative, students are very hands-on, Parent Teacher Association
members are engaged, and once the message goes out about smart farming, everyone in the community comes.
Setting up these gardens per site is done in three to four days, during which participants are trained on mixing the soil, setting water troughs, seedling establishment, and plant care.
And after three weeks they are harvesting, and there is no weeding, so that is really exciting for the students, and for the teachers the project does not divert them much from their primary role of teaching. The time the teachers have to spend in the garden is minimal, but the output is visible to all. So some teachers are also doing it in their homes. Students at boarding schools are saying they can’t wait to go home to try this. They want to teach their parents that there is another way to doing things.
Are other schools in Zambia planning to embrace the technology?
When we piloted the project with the first schools, we created a national WhatsApp group to keep track of information and advice, so for headteachers, when we got to their schools, we found that they have invited other headteachers just to learn. You find that everyone wants to adopt the system. The only challenge is the initial investment and the technical part.
They don’t have enough technical people to give them such skills, but at the start of the project we partnered with the Zambian National Science Centre (a department under the Ministry of General Education), so that people can always get technical help from them going forwards. The government has embraced the project, so we will see if it can scale up the project and include it in the school curriculum.
This article is part of Issue #5
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