Greenhouse Canada

Features Fertilizer Inputs
Inside View: October 2011

September 28, 2011  By Gary Jones


According to Mike Berners-Lee in his new book How Bad Are Bananas?,
fertilizer manufacture and use presents “a real carbon opportunity: up
to half a per cent reduction in global emissions [of CO2 equivalents,
CO2e] – it’s dead easy and has no side effects.”

According to Mike Berners-Lee in his new book How Bad Are Bananas?, fertilizer manufacture and use presents “a real carbon opportunity: up to half a per cent reduction in global emissions [of CO2 equivalents, CO2e] – it’s dead easy and has no side effects.”1

One ton of nitrogen fertilizer made inefficiently and used in excess, releases 12.3 tons CO2e. This is because the manufacturing process is energy hungry in terms of both heat and pressure, and much of the byproduct of the process is nitrous oxide, which is 300 times more damaging to the atmosphere than carbon dioxide. Given that about 30 per cent of the world’s nitrogen fertilizer is manufactured inefficiently in China, and spread very generously in the same country, this presents a good way to reduce our effects (globally at least) on climate change.

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THE BENEFITS OF NITROGEN APPLICATIONS
But this is not to say that all applications of nitrogen are “bad” and should be avoided. In Uganda, for example, it’s clear, as Berners-Lee suggests, that nitrogen fertilizer applied even very sparingly would return significant yield increases and so go a long way to helping reduce hunger. While in East Africa, I came across an agriculture system known as “Farming God’s Way.” While being more than just a technical system, Farming God’s Way links together three spheres: agricultural technology, sound management principles, and spiritual (Christian) philosophies. Check the website at www.farming-gods-way.org .

The main under-pinning principles of “Farming God’s Way” (recently renamed “Foundations for Farming”) are that farmers should:

  • Do things on time
  • Work to (high) standards
  • Create minimal wastage

In terms of the basic agricultural technological principles, “Foundations for Farming” is a conservation agriculture system, or minimal tillage, using the following concepts:

  • Do not plow.
  • Do not burn or incorporate plant remains (in other words, the mulch that is left during and after crop growth).
  • Practise crop rotations.

PLANTING FOR SUCCESS
Crops (maize, beans) are typically established on a 60 cm x 75 cm grid system, with rows across the land contour to retain rainfall and prevent rainwater run-off down the slope. Seeds are sown at these planting stations by “holing out,” meaning a simple hole is made by pulling soil down the slope to form a ridge below the hole, using the ubiquitous African hand hoe.

A fixed quantity (a teaspoon) of inorganic fertilizer or a 350 ml cup of manure or compost is then placed in the hole, covered with 3 cm of soil (to prevent root scorch) and the seeds sown on top of this in a straight line along contour (to provide spacing and reduce competition of seedlings).

A shallow (5 cm) layer of soil is added and the field covered with a thick mulch of leaves, twigs and drying grasses, before awaiting the rains.

‘YOU CANNOT MANAGE WHAT YOU CANNOT MEASURE’
So, back to the fertilizer. Since its beginnings in Zimbabwe in 1984, this simple farming method has generated amazing results across Africa. Part of the reason for this is the controlled use of manures, composts or inorganic fertilizers. All of these inputs are managed with a simple, repeatable, proven system. This is a significant step on a continent where organization is difficult and often not the accepted “modus operandi.” The manual for Farming God’s Way emphasizes that “you cannot manage what you cannot measure.”2

Perhaps there is a lesson for us all here. According to Berners-Lee, “the Chinese government believes there is scope for a 30 – 60 per cent reduction [in fertilizer use] without any decrease in yields [in China]. In other words, emission savings in the order of 100 million tons are possible just by cutting out stuff that does nothing whatsoever to help yield.”

This could be achieved by simply following the Foundations in Farming example of doing things to a high standard, without waste, and understanding that we cannot manage what we don’t measure. In our western agriculture systems, we often rely on expensive inputs. But honestly, just how much do we really measure their use and their effects?

  1. Mike Berners-Lee, (2011), “How Bad Are Bananas? The Carbon Footprint of Everything.” Greystone Books.
  2. Grant Dryden (2009), “Farming God’s Way Trainer’s Reference Guide,” p. 111.


Gary Jones is Chair of Production Horticulture at Kwantlen University, Langley, British Columbia. He sits on several industry committees and would welcome comments at Gary.Jones@Kwantlen.ca.


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