Keyhole Gardens

Following a story on BBC News that fellow blogger Sokari of BlackLooks had already picked up earlier in June (as well as Alison), our reader Zeno dropped in an e-mail, asking if we knew more about keyhole gardens.

Keyhole gardens?

Actually, I had heard about those Folkewall installations in Gabarone, Botswana the other day that are used for greywater recycling, but keyhole gardens were indeed quite new to me. Guess this also shows how many smart solutions still exist out there that will need to be rediscovered and put in use.

Keyhole gardens are a technique used to grow vegetables in a dry climate. They are actually a special form of raised bed gardens: circular waist high raised beds with a path to the center. Walled in by stones, there’s a basket made from sticks and straw in the center that holds manure and other organic kitchen waste for compost.
Since they look like a keyhole from above, they are often called keyhole gardens and also promoted under this name in Lesotho, where the charity organisation “Send a Cow” has been promoting the creation of these special gardens for some time now.

So what makes these gardens so special?

  • the surrounding stones retain the rich soils and keep it safe from erosion
  • the round shape retains moisture
  • compact size, even small plots can be used for gardening
  • raised beds enable the sick and elderly to help with the gardening work
  • center in the middle is used for composting and reuse of greywater (= reuse of nutrients)

“Send a Cow” also created a very informative website on their activies and published some valuable How-to-manuals for us to adopt this smart approach. Please also check out this funny animation on YouTube which puts it in plain enligsh comic style 🙂

Now I am only curious to know if we could also mix the greywater with some collected urine and use that as additional fertilizer. In any case, keyhole gardens are a very appropriate “technology” which certainly isn’t limited to countries with a dry climate.

Bio-Diesel From a Small Village in Sierra Leone

Makeni is a small town in Sierra Leone. Like the rest of the country, it is trying to recover from years of internal strife. Unlike the rest of the country, they have the Binkolo Growth Centre, a small industrial project near Makeni where the manufacture of small farm implements, tailoring, carpentry and blacksmithing takes place, and includes the use of disabled people. Two VSO volunteers, one from Kenya one from Canada, work to train and bring new ideas to the centre.

One such idea was to create a fuel replacement for their pickup by using local palm nuts, a by-product of the palm kernels, which are generally fed to pigs or used for fertilizer. Since diesel fuel for their truck runs approximately $5/gallon, it wouldn’t hurt to try.

Palm Nut Crushing Machine

It became clear that in our poor country the chief hurdles were getting the chemicals and the right equipment. The search was on for the chemicals and after quite a treasure hunt and more than a few bribes we managed to find 4 litres of Methanol and 5 kilos of Potassium Hydroxide (enough to make a good bomb I think)…

…Actually the whole scene was quite amusing. Here we were hoping to compete with the big oil producers in the back yard of a small village and using an untried collection of old car parts, old pipes and taps attached to a used chemical container, all put together in an image downloaded from the internet. Nonetheless we were fuelled by much excitement, with much of the local community looking on, wondering what on earth we were up to.

Read the rest of this great story, and see a lot more images, on Paul in Sierra Leone’s Blog!

The Team behind the bio-diesel project in Makeni Sierra Leone

The Truck running on bio-diesel

(hat tip Emeka)

Fighting Hunger, One Village at a Time

The Universal Nut Sheller (UNS) is part of the Full Belly Project. It’s really an amazing story about a device that has had a direct impact on a number of African countries. The story goes that Jock Brandis, an American inventor, was on a trip to Mali and saw some women who had been shelling peanuts leaving them with bleeding hands. This spurred him on to create a device that would help end hunger.


The Universal Nut Sheller in Africa
(Watch a video of a pedal-powered one in action)

How does it work?

The process works by centrifugal force and friction. The Universal Nut Sheller is basically a concrete cone within a cone, open at the top and bottom, with the interior cone being solid. The interior cone, or rotor, rotates on a shaft and has an attached handle (Note: only one moving part!). The user turns the handle around fast enough to spin the nuts to the outside through centrifugal force. The nuts fall between the surfaces and are rolled and squeezed, allowing the nuts and shells to fall through to the bottom. This mix of nuts and shells is then winnowed out, the old fashioned way.

Reach and Impact
According to the Full Belly Project, this machine is being used in 12 African nations, including; Mali, Uganda, Malawi, DRC, Gambia, Ghana, Kenya, Nigeria, Senegal, Sierra Leon, Sudan and Zambia.

The nut sheller is being used to shell more than just peanuts. As new villages take up the device, they turn it towards their own diverse nut shelling needs, such as jatropha, neem nuts, shea nuts or coffee.

Most importantly, he Universal Nut Sheller costs about $50-75 dollars to make, depending on the price of local materials, and will serve the needs of a village of 200 to 1000 people.

Like two past projects that we’ve highlighted on AfriGadget, this one is encouraging. Both the recently profiled see-saw power machine (possibly), and the KickStart pumps are based on the belief that sustainable economic growth comes through empowering local entrepreneurs to start, or extend, their businesses. In fact, the plans for the UNS are free and downloadable.

(Via Kaushal)

Street Meat Heater: A Simple Solution

Simon Kasiraba is one of many sausage vendors found in the cities and small towns throughout East Africa. He’s the prototypical micro-entrepreneur trying to make a living by supplying a need (food – conveniently available). He’s on AfriGadget because of the simple innovative solution that he employs to keep his food ready to be eaten at all times of the day – which is very important when you’re set up beside a bus stop.


Sausage Cart - Simple Heating for Street Meat

He keeps the meat warm using steam, with a simple charcoal heater placed inside the body of the sausage cart. The water goes into the pipe on the side of the cart, and floods a water panel directly underneath the meat. When it gets hot, the steam keeps the sausages warm, yet juicy. The cart cost him 14,000 shillings (about $200). He sells each sausage for 10 shillings (about 0.14 cents).

Here is a video of Simon showing me his sausage heating cart:


Images of the sausage heating carts can be found in the AfriGadget Flickr image pool.


Inside the Sausage Heating Cart

If you have any stories that would fit well on AfriGadget, contact us, we’d love to hear from you!

Water Harvesting by Roadside Plant Nursery

David Mwangi has run a roadside tree and plant nursery outside of Nairobi for four years. In Kenya, you have to work around the two seasons (unlike the 4 in the West). The rainy season where everything is fine, and the dry season where your plants will likely die. This gets even worse when a drought happens.


Roadside Nursery in Kenya

David had the idea to dig a ditch down the side of the road and channel that into two 2-meter deep water catchments. The water is used to support the plants during the dry season and he never runs out of water, even during a drought. He has also stocked the pulls with fish (Tilapia), that he and his workers eat. A third byproduct is that the rain water being diverted doesn’t further erode that part of the road.

It’s a lesson in simplicity married with low-tech ingenuity coming together for increased business profitability.

Here’s a short video, where one of my friends translates for David:



More pictures available at the Flickr AfriGadget group.

If you have any stories or pictures of African innovations and ingenuity, please contact us.