11. Growing cassava

In this blog I'm writing about our experiences buying and growing cassava.....

 A cheap, reliable energy source underpins successful pig production everywhere in the world.  Corn, wheat, barley, sorghum, rice and other grains fill this purpose in many countries.  In tropical climates cassava is a high yielding crop and is a major source of carbohydrate for humans and animals.  Indeed, globally, it is the third largest food source of carbohydrates after rice and corn.  It provides a basic diet for over half a billion people. When dried to a powdery or pearly extract it is called tapioca or manioc. It can also be used as a meal for poultry and pigs.

Cassava from a garden near
Komo - (lower altitude)

A multi stemmed plant, Cassava grows about two metres tall. The roots (tubers) are rich in starch. The leaves are a good source of protein and lysine but low in methionine and possibly tryptophan. They make good hay for livestock.  The tubers are high in Vitamin C and easily digested.  They contain about 30% dry matter but provide about the same energy value as wheat on a dry matter basis.  Their flesh is white or yellow.  There are bitter and sweet varieties.  Because they are cyanogenic they must be cooked, dried or the skin of the tuber beaten; except it appears, in Papua New Guinea, which has the good fortune to have planted varieties low in cyanide.  By chopping the cassava through a garden mulcher and fermenting it we further reduced any cyanogenic risk.

Cassava is a perennial crop that can be harvested as required.  It grows well in hot tropical climates, especially at sea level, up to about 1800 metres and as the last crop in a rotation. At Farm Alstonia, staff planted the crop in the dry season. They relied on residual soil moisture and then rain during the wet season to finish the crop about 10 months later although Miriam and Nerius assured me that some gardens would be ready in 8 months. Adequate water and fertilizer are necessary to produce sweet cassava and a less toxic crop.

As well as reducing cyanogenic toxicity, fermentation also removes other anti-nutritional factors such as those responsible for a goitrogenic effect. Our cassava silage had the same sweet smell you get with silage made from grass.

Newly planted cassava

The crop is harvested by hand by raising the mature lower stem, about 30mm thick, and pulling the roots and tubers out or the ground.  It is hard, physical work.  The stems are cut into 20 cm lengths and set aside for replanting before the wet season. The stems are simply stuck into the ground or partly buried.  It  doesn’t seem to matter.  The roots sprout quickly and the plant grows.

After harvest the tubers rapidly deteriorate unless they are processed quickly.  If not stored quickly they go black in minutes. Left attached to the stalk or buried they will survive.

At Farm Alstonia our staff already grew a few rows of cassava for their own consumption, so we decided to increase the size of the gardens.  Our pig house held 20 pigs.  It took us about 20 weeks to grow each lot of pigs, so we could produce, roughly, 40 pigs each year.  We needed about 20 tonnes of cassava. That’s at least 200 very big bags of cassava if they were filled to the top. The plan was to grow it ourselves, chop it up through the mulcher, ferment it and then feed it out after at least 2 weeks.  We thought it would last at least 8 months. I wanted to have enough cassava silage in the system to feed the current batch of pigs.  Depending on the time of year, I preferred to have a whole years supply ahead of me so that we wouldn’t run out.

However, it would take about six to eight months before our crop would be ready to harvest and I needed cassava “now”.    Around Port Moresby villagers only ever grew small quantities.  On one occasion when we were trying to buy cassava in the Gordons market in Port Moresby I followed a man carrying a big bag of cassava into the market intending to buy some.  He had two bags for sale. His total production. I wanted 100 bags.  He laughed at me.  Eventually we were able to buy 100 bags to feed the pigs from a local villager who planted a larger area than most, but we had to pay 100 Kinas a bag (about $40 Australian currency).  It was OK for a trial run but could never be sustained long term.  Eventually through contacts in the Gordon’s market we found Roger – or rather Roger found us.  He said he could organize as much cassava as we needed from local growers or growers on the Sogeri Road.

It is important that we bought kau kau or cassava at a price comparable to the price of wheat on an energy basis.  Mostly the local people trade small quantities so planting enough cassava to produce 100 bags of tubers is a lot more than they usually do.  Further, depending on the season they will be paying about 75 -100 Kinas per 100kg bag. Problem is most of them don’t know how much a bag should weigh so there is huge variation in what constitutes a bag. I thought it was anywhere between 50 and 100Kg.

In 2013 wheat cost about 1300 Kinas /tonne by the time it was landed in Port Moresby.  Given that wheat is about 90% dry matter and cassava is about 30% dry matter we could afford to pay about 433 Kinas per tonne for cassava. Over that price and we may as well use wheat. Even with the good price (14 Kinas /kg dressed weight) we received for our pork (about twice the price in Australia) the high price of feed soon took the gloss off it.  In our commercial pig farming operation it cost us, on average, about 2600 Kinas per tonne for feed.  The pork to feed price ratio was about 5.4.   A ratio of about 6.0 is break even.  Hence the cost of cassava needed to be about 400 Kinas per tonne or less for us to make any money out of pig production.  We knew that in time, as people grew more cassava and got better at it, that their efficiency would go up and the price would come down.  If it didn’t, there was no point going forward.  PNG may just as well buy all its food on the international market. Of course, where it would get the money from was anybody’s guess.  Under WTO rules food came into the country from Australia and New Zealand and elsewhere to the detriment of local farming businesses who could not compete; neither on cost nor quality nor reliability of supply. It didn’t seem fair.  Then again it didn’t seem fair that local consumers should be forced to buy a substandard local product that cost more than the imported equivalent.

I arranged to meet Roger at a local shopping centre one afternoon in September 2013.  He wore brown plaid suit pants, a matching waistcoat, dark grey shiny shirt and a flat cap.  He looked a bit swish. He was about 1.65 M, perhaps 64 Kg, about 35-40 years old although in PNG I found it hard to tell.

Patrick and Miriam told me that his day job was as a preacher, so I was hopeful that we could come to an arrangement that could serve us both well into the longer term.  If all went well, we would need a lot of cassava.  Roger agreed to supply 50 bags each weighing 100 kg. I wrote out a contract which we both signed and made a duplicate that we also both signed.  The price agreed was 80 Kinas per bag.  This was less than we had been paying locally but still unsustainable. I was hoping for 45 Kinas per bag, but Roger wasn’t having any of that price.  I needed cassava so had little option.  It was sure to be better quality than the rotten kau kau that we had been buying from the highlanders through the Gordons market. 

It was a frustrating experience.  We would never get a project to work if we had to pay so much for feed.  On the other hand, it was a supply and demand matter.  The villagers didn’t grow more cassava than they needed because they couldn’t sell it.  I thought that a contract for 100 bags at 45 Kinas per bag would be very attractive for the local villagers.  It represented about 1500 hours work or about 37 weeks work. It wouldn’t have taken that long to harvest two hectares of cassava. In a country where many were underemployed this seemed to be pretty good.  All very well for me to say that of course, but right now, today, they didn’t have any surplus and the 100 bags I wanted could only follow after it had been planted, grown and harvested in 10 months’ time. 

Today’s cassava at 80 kinas per bag was earmarked for the Gordon’s market, or me.  There were no pricing favours. About two weeks after we had signed the deal Roger called and asked to see me.  He had been in touch with his villagers and they had agreed to the terms, but he wanted a further amount to pay for shipping. I realized that I had not made it clear that this was included in my price, but the additional cost was minimal.  Transport is expensive in PNG. So is fuel.  So, I agreed to an extra 150 Kinas.

Roger made several visits to the farm each time wanting to negotiate and increase in price.  Miriam refused to deal with him.  On my next visit to Port Moresby Roger turned up with the truck fully loaded but demanded a further 10 Kinas per bag.  Someone had told me that in PNG the negotiation starts after the contract is written. It was true in this case.

Neither Patrick nor Miriam trusted Roger.  They wouldn’t deal with him. It was left to me to speak with him under the giant mango tree near the sow shed. 

“No deal”, I said.  “You can take your 50 bags home and sell it to someone else. Or we will pay you the agreed rate plus freight.”  

Roger begrudgingly accepted our offer.  The cassava was unloaded. We arranged for payment directly into his bank account.  Roger tried to claim that the funds were never paid but we were able to show him the paper trail of payment details into his account.  For a relatively well educated and well-spoken man, he was very difficult to deal with, but it was no different to the way business is done in PNG every day.  I was starting to understand the reasons for security people in numbers and multiple checking of goods, payments and receipts at the local trading stores.

I could see little future in trying to deal with Roger again so discussed further with Patrick, Miriam and Nerius the crop we were growing ourselves at Farm Alstonia. I really had no idea of likely yields and hence how much land we would need to plant.  It was an important element not only for our immediate needs but because I thought we might be able to test the idea of contract pig production near Port Moresby.  There the villagers would use cassava as their crop and it would be important to give them an idea of how much land they needed to plant. Globally cassava can yield as much as 30 tonnes per hectare but the range is enormous and depends on the country.  Various sources suggested PNG yields of about 8-11 tonnes per hectare.

 

Miriam's map of the cassava gardens at Farm Alstonia.
We measured each garden in paces.

I was interested to see if staff had any idea of the amount of land needed to grow the required 20 tonnes of cassava. When we talked about these quantities it became abundantly apparent that staff didn’t know how much to plant. Miriam and Nerius worked out how much cassava to plant based on their village experience from New Britain and New Ireland islands.  They used to cultivate a garden about 10 M x 10 M with rows about one metre apart.  Our first first garden of 100 M² harvested yielded about 1 tonne of cassava.  Based partly on this Nerius planted about 3900 M² that, based on a ten tonne/ha yield would be plenty. 

Miriam (left) and Yuti who looked after the cassava crop

While the tractor could plough the ground for planting the cassava cane, trimming the plants, weeding and harvesting all had to be done by hand. We hired Yuti, a Huli woman, whose brother worked on the farm. I found it hard to believe that this lean, diminutive, pleasant woman, her head always wrapped in a bandana, would be able to manage the seven plots that Nerius planted. 

Yuti planted them with cuttings from the last crop and kept them weeded. In all, in mid-2015, she planted 4481 cassava stalks.  With each one predicted to yield between 6 and 9 kg per plant the total crop should be at least about 26 tonnes. She never waivered from her conviction that managing the crop was well within her grasp.  She would, however, need help with the harvest.

Harvesting the first cassava crop at Farm Alstonia

In August 2015, the second year of the project, it all came unstuck.  It was an El Nino year, the wet season failed, and the drought ended our chances of a reasonable crop.  The ABC news report on 29th August 2015 stated,

“Hundreds of people died when PNG faced similar drought and frost conditions in 1997. In very remote areas, experts have said the death rate was as high as 7 per cent. PNG prime minister Peter O'Neill has said the current (2015) crisis could be even worse. More than 1.8 million Papua New Guineans have been affected by the recent extreme weather, according to Mr O'Neill, with more than 1.3 million of those in the "most at risk" category.

The cassava crop stopped growing when the moisture level dried up and the tubers put out additional sprouts as a survival mechanism.  Patrick tried to save the crop by irrigating with a little pump from the lake next door, but the owner of the lake refused us permission to pump.  It was too much for our little garden and the season.  In the end we managed to grow about half our own feed.  We bought in the other ten tonnes from local suppliers.

When the rain eventually came in 2016 Yuti cut off the new shoots with her bush knife and eventually the crop could be harvested but by that stage we were packing up the project, and no longer had the staff to harvest the crop, no funds for premix, nor any pigs to feed it to.  

Next blog... Our field days - getting the word out.