Food: Organic growth?

Spray irrigation in field Irrigation was one of the factors affecting relative performance of the different crops

The vexed question of whether organic farming offers significant benefits over conventional methods has been raging on for years.

To the outside, it often seems to take place in an environment where entrenched beliefs are more important to some protagonists as evidence.

A paper in the journal Nature this week aims to put that right, with a comprehensive and rigorous analysis of studies done on crop yields.

The researchers, from McGill University in Canada and the University of Minnesota in the US, looked for studies that met pretty stiff quality criteria.

To be included, a study had to compare organic and conventional planting across similarly-sized areas, had to report on the sample size and error margins, and had to use organic methods that complied with the guidelines of certification organisations (such as the UK's Soil Association).

Organic carrots Organic enthusiasts maintain there are taste advantages as well as boons for wildlife

The headline conclusion is pretty unequivocal; across the board, organic farming produces lower yields than conventional methods, by about 25%.

For fruit, the difference is marginal, just a few percent. But for vegetables, organic yields are about 33% down on conventional, with barley and wheat a little lower still.

There are further differences depending on what type of soil is in play; and there's a steer that some of the enhanced performance of conventional cropping comes through better irrigation.

There's a growing body of evidence showing that in order to provide the extra food needed by the bigger and richer human population of the near future - a doubling of demand by 2050 - without destroying forests and wetlands, farming needs to be made more intensive.

So on the face of it, this latest analysis is a vote for conventional methods above organic.

This would be a slap in the face for people who choose to eat organic food because they believe it's better environmentally - though not for those who choose on the claimed health or taste benefits.

But the fact is that yields are just one aspect of the much larger debate about the farms of the future.

Conventional farming methods using conventional fertilisers are adding active nitrogen to the soil, which tends to move to other places - lakes, rivers, seas, the air.

And according to the Planetary Boundaries concept, the nitrogen cycle is already one of the places where humanity has already broken through the "safe limit".

Intensively reared turkeys Farming systems are about a lot more than yield - welfare, of animals and farmers, is also key

Conventional farming is likely to be harder on insects such as bees - which we know are already in trouble in many countries, partly through use of insecticides that organic farming systems should avoid.

More complex still is the social side of agriculture.

In some countries if not in all, organic farms tend to be smaller than their conventional neighbours.

They're likely to be less mechanised, and to produce goods that command higher prices.

All of which is very good for the social side of agriculture - boosting employment (in the same way that artisanal fishing provides more jobs than the industrial kind), promoting local ownership of land and, in the poorest countries, mitigating against land-grabs.

Just to make things more convoluted, food production and distribution is now an internationalised system.

If Western consumers demand organic food among their imports, is that foisting an inappropriate standard upon growers in poor countries, or is it potentially helping to set better standards for farmers' health and welfare in the exporting country?

It's a rich smorgasbord of issues alright. And yields, as you might say, are not the only fruit.

Richard Black, Environment correspondent Article written by Richard Black Richard Black Former environment correspondent

Farewell and thanks for reading

This is my last entry for this page - I'm leaving the BBC to work, initially, on ocean conservation issues.

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  • rate this

    Comment number 1.

    The problem is, high intensive farming equates to high pollution, can we afford to carry on pumping high energy requirements in to our food production?

  • rate this

    Comment number 2.

    The problem with modern farming is yields and profits are put before health. Its not just farming either, its production too.

    Here is an example, regular none organic orange juice is aseptically stored, with the oxygen stripped from it, for up to a year. Ethyl butyrate is then added to give the juice its "fresh flavour back". No requirement of the manufactures to list this added ingredient!

  • rate this

    Comment number 3.

    @Tom - no, the problem is high intensive human populations breeding like flies. Why is there so little discussion of decreasing demand rather than increasing provision?

    Yes, certain agricultural practices could & should be improved. But it's about time we took a look at consumption too, because the farmers are only trying to provide for the rest of us.

  • rate this

    Comment number 4.

    2. General Rab

    Organic used to be "regular", but not anymore. Thanks to cancer creating malevolent companies like Monsanto

  • rate this

    Comment number 5.

    As the cost of fertiliser increases organic will become more attractive.I wonder if the same amount of money was spent on improving organic methods as on conventional would that gap close anyway.

  • rate this

    Comment number 6.

    There are a number of problems with agriculture as it is currently practised, such as the depletion of resources like oil, the absence of abundant, affordable petroleum products will impact our ability to utilise pesticides and fertilizers as we have for the last century.
    There are techniques, such as those evolved by Masanobu Fukuoka and Sepp Holzer, which might contraindicate these findings.

  • rate this

    Comment number 7.

    Study methodology is key. If the study runs for 3 years or less, conventional / chemical methods win. If the study runs for 4 or more years, in the 4th year the results are about even - but in the 5th (and subsequent) years, organic yields are higher. The reason for this is that chemical means deplete the soil of organic components and it takes a while to replenish them via organic cultivation.

  • rate this

    Comment number 8.

    Yes, there are distinct, if not criminally significant problems with
    both conventional and organic farming practices. Key nutrient
    suppliers in both camps, chronically misrepresent their materials as safe to use in farming. Heavy metals are the most
    pressing toxins in food.

    There is a remedy: ultra purified nanoparticle nutrients will replace toxics currently in practice.

  • rate this

    Comment number 9.

    Figure 3.4 of the Stern Report indicates wheat yields decreasing as air temperature rises beyond 30C or so. The figure is taken from Wheeler et al, but Stern deliberately omitted the all important rising CO2 effect, which showed a clear Hockey Stick i.e. more CO2 & more temperature = more wheat.

    Sterns graph also omitted data that suggests yield also increases further up the temperature scale

  • rate this

    Comment number 10.

    One word, sustainability!

    Until conventional farming acknowledges that farming does not take place in a lab, and top soil, specifically the water soluble fulvic acid portion, is absolutely a vital resource, there will be sustainability problems.

  • rate this

    Comment number 11.

    What is "organic"? Who defines it? Why? Isn't "conventional" rather varied? Shouldn't we be using the best scientific methods to determine the best way to grow enough food for everyone?

    @LexingtonNC: The Broadbalk field at Rothamsted has been growing continuous (non-organic) wheat just fine for well over 150 years.

  • rate this

    Comment number 12.

    erm.. Richard this is an interesting story for all the wrong reasons..the scientific studies should be comparing between best yield, drought resistance, etc. varieties of standard crops and those of the GM varieties..No-one claims organic gives higher yields..the reason for eating organic is because (in season) the crops often taste better and it reduces monoculture and chemical loading in farming

  • rate this

    Comment number 13.


    Lammy, lammy, lammy.

    "the reason for eating organic is because (in season) the crops often taste better and it reduces monoculture and chemical loading in farming"

    It's not often we agree and I'd go one step further. Food grown hydroponically tastes (expletive omitted) awful imho

  • rate this

    Comment number 14.

    @11 ..'What is "organic"? Who defines it? .." peterdl

    Richard linked in the article (TLDR?) to this organisation -


  • rate this

    Comment number 15.


    Always nice to be able to agree :)

    However can't agree with you @9..unsustainable water extraction is not factored into that model, for example..the Sahara is hot, not great for wheat growing though and CO2 would not change that.. besides, according to contrarians humanity cannot add CO2 to the atmosphere in a manner that would affect climate..which means you cannot have it as a 'benefit'..

  • rate this

    Comment number 16.

    @15 Have to agree with you again on the water issue. I'm beginning to think we should get married! lol

    But then you say added CO2 can't be a benefit because sceptics don't accept adding CO2 to the atmosphere affects climate.

    1st of all, most thinking sceptics argue on the amount of effect not the actuality. CO2's ability to raise temperature is well known

    2nd, why can't it be a benefit?

  • rate this

    Comment number 17.

    More food MAKES more people,,
    this is a race we cannot win !

  • rate this

    Comment number 18.

    Organic vertical farming in greenhouses is absolutely the future. There'll be lots of energy required but energy issues will be figured out soon enough. Consistent yields are better than bigger ones plus it'll save the health of the crop sprayers and wildlife.

  • rate this

    Comment number 19.

    Poor old Nitrogen, it's becoming the new Carbon. I wonder which element is next.

  • rate this

    Comment number 20.

    Wow, a lot of passion in the farming business. I use CO2 as a

    propellant for foliar sprays. Opens stomata. Works good.

    Viva Pharmaceutical amino acid chelates outta help a lot.

    Nano Iron Phosphates inhibut Cadmium uptake from soils.

    Otherwise, we suffer from anagnosia. Better learn the truth

    about the origins of heavy metals and their hyperaccumulators.

    I love dirt. But, not its toxics.


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