Growing stronger

Date:9 August 2018 Author: Brendon Petersen Tags:, ,

We’ve seen urban agriculture try to take root before. This time, though, it’s being driven by the youth and is finally emerging as the key to our continued survival on this planet as well us the gateway to colonising others. Lindsey Schutters investigates.


Urban youth getting into agriculture: it’s a contrast as stark as the fragrant basil farm fighting for attention against the city skyline.

Greenhouses on rooftops aren’t a new development for South African cities. Pilot projects date back to around 2010. Hydroponic urban agriculture also stretches back quite far, with a sharp spike in the mid-1990s attributed to regualr references in American rap music.

Nhlanhla Mpathi’s fitted Under Armour cap just barely contains his dreadlocks as he enthusiastically explains the story of how he ended up tending herbs on top of the Chamber of Mines of South Africa building (the one on Marshall Street in the CBD, not the one at Wits).

Mpathi was identified by innovation incubator Wouldn’t It Be Cool (WiBC) and is now a key part of the latest pilot project, in partnership with the City of Johannesburg, meant to stimulate growth in the CBD. The plan, currently, is a three-year-one: WiBC funds the first year and the target is around 100 farms. “Year one is a rollout of 15. Then we use that revenue to fund the next set and the next,” explains project manager Brendon Martens.

Back on the rooftop, Mpathi is busy dosing the rows of basil. His produce isn’t used in that idealistic way where he goes down to a street corner to hawk leaves, but is rather traded at Joburg Market – the biggest fresh produce market on the continent and member of the World Union of Wholesale Markets. He has also, on his own, struck supply deals with the café downstairs and a couple of hotels.

“What Nhlanhla is growing is basil. Traditionally that is imported to the Johannesburg market and sold there. About 3-4 per cent of that value stays with the marketing agent, but the rest goes to whichever province the produce comes from. But that value comes in and leaves,” says Martens. “What we’re doing now is pulling that 97 per cent back to the inner city, which would have never happened before. And it’s that little drop that creates a multiplier effect (the economic concept).”

WiBC doesn’t teach the growers how to farm, but merely mentors them and secures the site for them to set up operations. “We provide the market access. So, if the marketing agent comes to us and says there’s a shortage of green peppers, for example, in three to six weeks we could have gone from planting to delivery. Whereas with field agriculture you’re looking at eight to 10 weeks. As soon as we receive the market information we tell the farmer, change to this product, they do it and we go to market and get a good price for it. When the other guys come in with their trucks then the price drops and we move on to the next product. You need to do it from a holistic perspective. You’re not just growing, you’re running a business.”

Gauteng Premier David Makhura has indicated that he wants rooftop farms on all government buildings. The standard model will be 100 m2 farms with 3 600 plants. That’s a R500 000-per-year business.

Mpathi is eloquent on the business of hydroponics. “I got my business training from them (WiBC). So you might look at me as a farmer and think that I’m selling a crop, but I’m actually selling something that is specific to my market. What you find with a lot of hotels is that they go through seasonal patterns. Basil might be trending this month, but might not be trending during winter. So they have to keep basil in storage for longer. Via hydroponics we can solve that problem.

“We can feed the basil with nutrients and elements that will make it last longer without it being refrigerated. For example, the mint that we grow is very specific in terms of flavour and shelf life. More than anything else, what I have found out from sitting down with these more premium clients is that usual suppliers’ produce don’t have long shelf life and the nutrients are minimal.”

His rooftop farm is based on the nutrient film technique (NFT). In this process, a shallow stream of nutrient-rich water is circulated past the bare roots of the plant. This system ticks all three boxes that determine healthy plant growth (water, oxygen and nutrients), is compact and scalable. The only downside is that channel length is curbed at around 12 metres because the nitrogen depletes past optimum levels at greater distances.

NFT was developed in the 1960s by Dr Allen Cooper, a scientist at the Glasshouse Crops Research Institute  in the UK, and codified in his 1979 book The ABCs of NFT. Dutch farmers were particularly critical of the negative effects of NFT; re-circulating water can spread disease quickly between plants if not filtered properly. However, there been a lot of research and development done in the design of water channels and crop spacing to mitigate these potential issues.

NFT Hydro, funded and owned by Cape Town-based husband and wife William and Lynn Gunning, is making big strides in channel design. The market is saturated with modified gutter pipes from the likes of Marley, but the Gunning company is engineering specifically for hydroponic challenges and gaining an international foothold on the African continent and, recently, in Kuwait.

William Gunning is a serial entrepreneur from KZN who started out doing fax-based mass marketing and then branched into software development. Lynn is from the financial services industry and has worked in international offices at some of the world’s leading firms.

“How my system works is water gets pumped from the sump up to the channels and circulated back to the sump. I can manually control the flow of each individual channel and dose into the sump,” he explains.

These NFT systems save around a minimum of 80 per cent of water as a result of the recirculation. Better water treatment and filtering can bring it closer to 100 per cent efficiency; at that point, the only losses come from evaporation or what the plant is actually using. Nutrient dosing can also be optimised for the specific type of plant, growth period and growth rate. Other benefits of hydroponics are longer plant life cycles, better yield, longer growing seasons and higher-quality produce.

“What I’ve been doing here is micro harvesting,” says Mpathi. “That’s where you come in every third or fourth day to harvest. I’m growing four different types of basil. if you want to compete at City Deep (Joburg Market), you need to bring something special. These crops allow me to bring different flavours to the market.”

What we see going into the market usually is mostly grown in open fields and doesn’t really contain a lot of natural nutrients, he says. “My agent told me that he can keep my produce for nine days without going into cold storage. It turns super black on the ninth day and you can’t sell it really after the seventh day, but that’s a long shelf life.”

On top of the plant roots is a layer of tiny balls: the growth medium. It’s expanded clay that absorbs excess water and is non-nutritive. Leafy greens thrive in an NFT system, but there are growth mediums in which you can suspend other crops. Those mediums allow for only the root ends to be exposed to water.

Agriculture has been practically a lifelong activity for Mpathi. At age seven, he was tending to his grandmother’s garden and experimenting with plant propagation. “I haven’t even turned 30 and I’ve already grown everything that can grow in South Africa. It started of fwith flowers and shrubs; then I moved on to trees and fruit trees… We had an avocado tree at home; I didn’t grow it, but I understand the process from germination to aftercare during winter. I’ve grew aromatic herbs and distilled lavender for a science project in grade 11 – my own set-up. I’ve grown a lot of things.”

Home is in Kagiso and his grandmother’s backyard was his playground. He describes it as four or five times the area of his current farm and the front yard was bigger, populated mainly with flowers and trees. From there he expanded into mushrooms and spices. His hydroponics career has been much shorter, though. Four months  at the time of this interview, to be exact.

“The initiative plugged me into this (hydroponics). I was part of another WiBC agriculture project in Sophiatown; that’s where I met Brendon and he got me involved. I was brought in to start the proof of concept to show that urban gardens can be sustainable business models and create jobs. It can be done and it’s going to be a big success. It’s just a matter of scaling up and finding the right people.”

Importantly, WiBC identified someone with 20 years of growing experience and then equipped him with the business skills to turn his passion into a career. The proof of concept site isn’t really commercially sustainable, but at the scale that it will evolve into it is a tidy business.

“You’re sitting on a R50 000 production head and then you can get in R150 000 for the crop. You’re only using 30 per cent of the gross to run the farm, so if you can plug into deals where you just grow and harvest and the client comes to collect then you’re golden.”

“Once you’re on a high technological level with advanced pumps and filters, you can run the same water for up to six months with hydro without having to refill” – Mpathi


“Charging the current electricity rate for the inner city, if I was paying my electricity it would total R273,95. And my water bill is R74,14.”


“In the future, instead of harvesting the channel I’ll just pull it out and plug it into the delivery van so the produce is still growing when it reaches the client. Get it while it grows, that’s the tag line.”


Growing on top of buildings is an important step to securing food supply for the estimated nine billion humans who will be inhabiting this planet at the middle of this century. As things stand, around 10-11 per cent of land mass is devoted to crops (roughly the land area of South America) and between 17 and 23 per cent (about the land area of continental Africa) is used for livestock.

Why can’t we grow on the rest of Earth’s land mass? Because around 57 per cent of it is uninhabitable and we already built cities and urban areas on three per cent of it. Humans could waste less food, but even if we squeeze a meal out of every morsel we will only reclaim around 30 per cent of the total food produced. That isn’t really a practical undertaking.

Adding 25 per cent more mouths to feed to a world ravaged by the effects of climate change is going to far exceed the supply. In 2012 the United Nations Development Report noted that one in four households in sub-Saharan Africa cannot access adequate food. The 2007 Intergovernmental Panel on Climate Change noted in its fourth assessment report that Southern Africa has higher climate change variability and predicted severe and far-reaching impacts on livelihoods. That same report predicted a subsequent decline in agricultural activity between nine and 21 per cent in the region by 2080.

A big part of that decline is brought on by a 2˚C rise in precipitation temperatures that will see a halving of stable food production. Maize, sorghum and rice will be particularly affected. The effects of global warming alone are putting up to 170 million people at risk of hunger in southern Africa by 2080.

The World Bank confirmed our deepest fear in a 2016 report, which found that whereas crop production grew by 1,05 per cent on average, the population increased by an average of 1,27 per cent from 1996 to 2016.

President Jacob Zuma prioritised food security in his 2014 State of the Nation Address, citing Section 26 and 27 1 (b) of the Constitution, which grants the right of access to sufficient food and water. The Climate Adaptation and Mitigation Plan for the South African Agricultural and Forestry Sectors (Government Gazette no 38851, 3 June 2015) noted that the effects of climate change on our country sometimes exceeded the mean rate of global temperature rise since 1950, evidenced by a decrease in extreme cold days and nights (by 6 and 3,7 respectively) and an increase in extreme hot days and nights (by 8,6 and 8,2 respectively) between 1961 and 2000.

Local rainfall data from Jonkershoek show a decline of 14 per cent and a further decline in the rainwater runoff of 20 per cent, resulting in a total average 500 mm loss in rainfall per year since the research began more than 70 years ago. This is significant because of the correlation between staple crop production yield and rainfall. These are devastating numbers, given that agriculture contributes up to 21 per cent of South Africa’s gross domestic product (GDP) and is responsible for 30 per cent of national employment.


An individual is classified as food insecure if he or she receives fewer than 2 261 kilocalories a day, equivalent to a food spend of about R220 a month.

There is a 1,16 per cent decline in maize production and a half per cent decline in wheat production for every 1 per cent reduction in rainfall.

Tanzanian researchers argue, however, that education – or rather lower education attainment – is that country’s biggest cause for future food insecurity.


On the premium end of the food consumption market there is an even bigger problem: restaurant and gourmet cooking menus are becoming ever more exotic with the continued rise of foodie culture and celebrity chefs. Although there is a strong niche focus on eating local, the lure of foreign cuisines is strong and retailers are forced into casting ever wider supply networks to feed this appetite for international goods. Food miles are increasing, which means greater individual carbon footprints.

But even a protein as basic as chicken imported from the US travels more than 13 000 km to reach our shores – and then out-compete our local suppliers for price. The energy needed for that journey from the fossil fuel to the refrigeration is a massive draw on finite resources.

Food miles don’t tell the full story, though. Most of food’s carbon footprint and ultimate environmental impact comes from the production process. Transport contributes only about 10 per cent of overall emissions. That said, importing food can sometimes result in significantly lower carbon emissions, especially when coming from a region with the correct climate for the produce. Tomatoes imported from Spain to Denmark produce almost 500 per cent fewer emissions than it takes to grow tomatoes in Denmark.

But thanks to the extra-secure food situations in the premium market, the opportunity exists for local rooftop growers to hyper-localise production of premium produce and net tidy profits.

Hydroponics is currently economically challenging for growing grains and, to a lesser extent, root vegetables. But servicing the leaf-grazing low carb and vegan cultures is something these growers thrive on. That, and upmarket kitchens that serve large volumes, like at large corporates.

A few blocks away is the expansive FNB building. Thousands of employees buzz around this financial hive and on the roof is a 100 m2 area that serves the company canteens. The project is doing so well that it is expanding to another section of the roof. Former chartered accountant Mapaseka Dlamini is the queen of this realm and she wants to run six similar colonies by the close of 2018.

FNB produces enough food to feed the entire Bank City and now there are plans to take the electricity off grid as well as to harvest the natural spring water flowing underneath the building. Taking 2 500 employees and four entire buildings off the grid would be devastating for the city, but wonderful for corporate image.

“I’m actually an accountant, but after completing my CTA level 2 in 2012 I decided that it wasn’t for me. I’ve done work with auditing firms like Deloitte, so I could understand what was expected of me. I wasn’t getting job satisfaction because I was working at the same time that I was completing my Honours doing supply chain and finance. Then I decided ‘Let me invest financially and non-financially in agriculture’.”

Dlamini’s path into hydro isn’t as serendipitous as Mpathi’s, but that’s kind of the appeal. After making the decision to get into agriculture, she found a mentor in Bronkhorstspruit and goes every weekend to work on the farm, gaining experience in crop and egg production. Her dad did small scale farming and used to sell vegetables, but there are no solid roots (excuse the pun) in food production or growing.

“When he (her dad) left off working for someone, he actually started a vegetable and fruit company. Some of the stuff he wouldn’t buy, but would actually grow them in the yard. One of my chores was to water the garden, which I hated. But then I was being programmed to love nature and understand plants without realising it.”

Dlamini lost her first R100 000 in Bronkhorstspruit and chalks it up to not having the business or interpersonal skills and also trusting someone without a contract. The couple that was mentoring her developed their land with her money and then wouldn’t sign a contract. From there she invested in a plot in Centurion as a stepping stone. An application for land followed and was granted in 2015: five hectares on a large farm in Diepsloot.


The problem with land grants, though, is that very rarely is the title deed handed to the recipient and then farmers can’t secure loans. This happened to her as well as being poorly treated by the Co-op.

“I was also granted a tunnel by the NYDA (National Youth Development Agency) that is still on that farm. But I encountered other socio-economic issues. There was a co-operative in existence already and they gave me a hard time. They felt threatened by me, even though they weren’t in production at the time. They thought I was being funded by someone when, in actual fact, everything was being funded by me from my salary.”

Dlamini explains how she had to fight for the ownership of the land and how, after eventually the social development initiative issued a land contract, the head of that department then refused to sign it. These problems stem from the improper handover procedures and are the canary in the coalmine of failed black farming initiatives.

“The land was still under Joburg City Properties, or something like that, and so I couldn’t sign a contract with social development because they don’t own the land. And then I got stuck. I decided this year that the system was swallowing me. Poor land access, insufficient co-operation and cash flow problems because I had to be on the farm full-time.”

She then met Nicky van Rensburg from the University of Johannesburg and was introduced to the initiative that strives to introduce technology and agriculture into the city. There was a building available and they needed a farmer to start. Luckily Dlamini was at an advanced state in research into hydroponics.

“I was supposed to be in production on a Doornfontein building in June already, but then there were hiccups. I found out that FNB was doing hydroponics on its rooftops and I asked to visit those. When I got here there was only spinach, but they were not maintaining it – it’s actually a facilities management project and not their primary business.”

Dlamini realised that here was a loophole. She turned that into an opportunity to establish herself while the Doornfontein chesspieces were being moved. She drafted a business proposal detailing how the site can be used to groom horticultural graduates and how to use it as a supply chain for the kitchens.

“They were just planting and now we’re trying to set up a proper production plan. The iceberg lettuce is what they use daily, but occasionally there are executive functions and they use the gourmet lettuce. We’re changing the farm to cater to what they’re using in the kitchens. Obviously it won’t be everything, but the bulk of the leafy greens and herbs is what we’re trying to grow for them.”

Her company is now contracted to FNB and it employs three full-time staff horticulturalists to assist with propagation and harvesting. Dlamini’s aim is to upskill them to start their own farms. FNB has also prepared the roof across the road for expansion purposes.


Other drawbacks Dlamini encountered when open-field farming is that those farmers are contributing to the rising sodium levels in the ground. Years of fertilising is changing the chemical and elemental composition of soil and negatively impacting yield.

Urban agriculture is also an effective way of controlling pollution in cities. The more energy expended in a city, the more heat is released, which is perfect for certain crops. Those crops also soak up a significant proportion of carbon from the microclimate, causing a cooling effect.

The inherent efficiencies of the hydroponic process result in invaluable savings on resources and these farms are not limited to roofs, but thrive in indoor settings, too. NASA has long been trialing hydroponics as the answer to extraterrestrial farming, with positive results.

The future of agriculture is changing and so are the faces of the people who produce our food. Devastating weather patterns and farm murders have turned many capable land workers away from what has been a generational vocation. Our world is staring down a food crisis on a scale that has never been seen before. These growers are the first seeds that will sprout into the vine that will help us escape from the hole that we’re in.

What is most exciting about hydroponics is that it improves dramatically with the advancement of technology. Many of this new crop of urban growers are connected via a locally developed mobile application called KHULA, which monitors stock levels and connects them to premium clients.

Major developments are happening in growing methods for different types of crops. Soon the start up costs for more energy-dense produce (think root vegetables) will be low enough to make it a viable alternative for single entities such as Mpathi. That could convert consumers to the technology and allow many more people to take charge of their personal food security by growing at home.

This is a start. Pockets of activity are cropping up across the country. There’s a thriving growing community inside old buildings in Woodstock next to the Cape Town CBD. The Cape’s Atlantic west coast is expanding at a rapid rate and commercial hydroponics projects are popping up all the time.

Even from a retail perspective, there is now a growing culture of hyper-localisation: smaller independent merchants can source exceptionally high quality produce from a hydro grower on the roof of the building that they’re in. The merchants can then even grow the food themselves.

It’s an exciting time to be alive.


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