There’s no single, definitive answer to this question, because environmental impact can be measured in so many different ways, and because the relevant research is a long way from comprehensive. However, according to most nonpartisan summaries of the scientific evidence – including, for example, one by staff writers at Nature and another by the government – organic farms are certainly more environmentally friendly in many ways. Compared with conventional farms, they tend to encourage greater biodiversity, such as insects, birds and other wildlife. They also tend to create less global-warming CO2 per kilo of food. Organic farms tend to generate less waste, too. In some areas, such as phosphorous run-off into streams and the all-important question of soil health, a lack of long-term comparative research makes the benefits difficult to prove beyond doubt, but, according to Nature, “many studies” suggest that organic production lives up to its promises.
That’s not to say that organic is necessarily the most eco-friendly farming system in the world – for now or for the future. Some scientists advocate a middle ground that builds on organic concepts but doesn’t rule out all synthetic inputs or GM processes – some of which, they claim, are less harmful (both to the environment and to health) than the “natural” alternatives. Still, this middle ground isn’t something that’s being widely adopted and it’s not something that we’re offered in the shops. For now, the choice is basically between the produce of “conventional” or organic farms, and the latter are indeed better environmentally.
But even if organic farms are a good thing for the environment, that doesn’t necessarily mean the same can be said of the organic food we buy. At least, not according to two arguments often made by critics of the organic movement. The first is that a huge amount of organic produce is typically flown or shipped from the other side of the world. This contributes unnecessarily to climate change, via the CO2 emissions of the planes and boats that transport it. It’s a fair point – Europe and North America account for practically all organic food sales, but only a third of total organic production, the rest being imported from Asia, Australia and Latin America. But it’s also perhaps an irrelevant point: a criticism of food imports as a whole, not organic farming. If we grew more organic food at home, there’d be less need to import it.
The second argument is that organic farms tend to produce less food per hectare than their more industrial counterparts. This is a pivotal issue, because it suggests that if everyone went organic we’d either face global food shortages or be required to clear vast areas of forest to make room for extra farmland – which of course would be an environmental disaster. So could organic farming produce enough for everyone without extra land? We’ll discuss that question below, but first it’s worth touching on one final environmental conundrum about organic agriculture. If organic farms produce less from each field, then they require extra land which could otherwise be used to grow renewable energy crops such as wood for heating and electricity generation and switchgrass for cellulosic biofuel. Arguably, then, it might reduce emissions to employ high-productivity (but environmentally sensitive) farming to produce a mixture of food and energy crops, thereby removing the need for some fossil fuels.