Ten things you should know about soil


Interesting facts about soil – article originally published here, by the Sustainable Food Trust.

Along with air to breath and water to drink, soil is one of our most important natural resources. Without it we would starve. However, due to poor farming practices, we are using soil at a completely unsustainable rate. The United Nation’s General Assembly has designated 2015, the International Year of Soils, to raise awareness of the urgent need to switch to sustainable soil management. If we do not make major changes to farming methods, food production will decline in future, instead of rising to meet the needs of a growing population.

Most current food production methods do not nurture the soil. Instead they exploit it, as if it were an infinite resource. As a result, 24 billion tonnes of soil is washed or blown away every year. That’s equivalent to 3.4 tonnes for every adult and child on the planet, every year. As well as being eroded, soil is also being degraded – losing its organic matter and structure – a process which ultimately turns 30 million acres of food producing land into desert every year.

Soil isn’t just important because it is the source of our food, it also plays a vital role in regulating the climate, providing clean drinking water and supporting plant and animal biodiversity.

The situation will only improve if we all understand what is going wrong and why, and what needs to change. There are many inspiring examples from around the globe of farmers who care for their soil, as well as examples of how once degraded land and even desert, is now producing food and sustaining local communities again. However, there are many more examples of abused soils in serious decline.

In this International Year of Soils, the Sustainable Food Trust will be returning to soil many times. We start with an introduction to this extraordinary and life-giving natural resource.

  1. Over 95% of our food comes from the soil. The quality of soil influences the quality of food, especially in relation to the content of important trace elements, such as selenium and zinc, and arguably also in relation to taste.
  1. A spoonful of healthy soil can contain more living organisms than there are people on the planet. The more fertile the soil is, the more organisms it has living in it. These organisms include bacteria and fungi, as well as larger soil creatures like nematodes, earthworms and ants. All are important for the health of soil.
  1. Soil is a mixture of minerals from rocks (45%), organic matter derived from decaying plant and animal material, plus the tiny living creatures in the soil (5%) – along with air (25%) and water (25%). It takes approximately 500 years for 1 inch of soil to form.
  1. Soils still contain more carbon than the atmosphere and all the world’s forests combined. Soil is one of our key defences against climate change because of this. The healthier the soil, the more carbon it holds.
  1. Soil organic matter is about 50% carbon. Humus is dark, stable, organic matter in healthy soils. Each gram of humus can hold twenty times its own weight of water, allowing soils with high organic matter to act as a sponge to soak up heavy rain and continue to provide moisture for crops during dry conditions.
  1. To increase humus levels by adding organic matter, it is vital to compost it first in an aerobic way to introduce oxygen before adding it to the soil.
  1. Most cropland globally has lost 30-40% of its organic matter. Well managed grassland that is not overgrazed generally rebuilds organic matter.
  1. Professor John Crawford of Rothamsted Research has pointed out that, at the current rate of degradation, we only have enough soil left globally to provide food for another 60 years. Soil degradation in countries with temperate climates is less severe than in some parts of the world, but researchers at Sheffield University claim that even in the UK we only have enough soil left for another 100 harvests at current rates of decline.
  1. Grapes of Wrath by John Steinbeck tells the story of families that had to leave their land and become migrant workers due to soil erosion in the 1930s. The severe soil degradation in the ‘Dust Bowl’ was caused by unsustainable farming practices which replaced native deep-rooting long grasses with continuous cropping of mostly wheat and led to three million people leaving farms in the praires of North America and Canada.
  1. History shows that civilisations, like the Summerian society in Mesopotamia (the world’s first literate culture) which flourished from 3,000 BC, came to an end because of over-cropping and over-irrigation of their soils. Irrigation in hot countries is a major cause of salinisation – the build up of salts in topsoil, because evaporation prevents minerals being taken down to plant roots. As US President, Franklin D. Roosevelt said: “A nation that destroys its soil destroys itself”.

Slow Food founder Carlo Petrini in Scotland


Went to an inspiring talk by Carlo Petrini (organised by Slow Food Scotland and QMU Gastronomy) this week, also featuring fantastic talks from Mike Small (Fife Diet) and Denise Walton (Peelham Farm).

Some news coverage here.

Just joined up and looking forward to participating in more Slow Food events in Edinburgh.

“If you start with food, you arrive at freedom” (Carlo Petrini, Feb 2015).

First world problems: Disliking food


By Alicia Miller and originally published on 29 June, 2014 on Sustainable Food Trust website here. I have just started to get a veg box, and am (mostly) enjoying cooking and eating the new and different veggies in the box.

“Running a vegetable box scheme tells you a lot about people’s eating habits and their relationship with food. People love the idea of getting a fresh, local vegetable box every week. When they find our farm, they say ‘it’s so fantastic you’re here!’ But when it comes down to the reality of getting a box of vegetables that they have to negotiate each week, for a lot of people their vegetable romance suddenly becomes troubled.

We always give people two opt outs in our boxes – they can tell us two vegetables that they don’t like and don’t want. I can always tell whether a new box scheme customer is going to make it through the first month when I ask them about what they don’t like. If they hesitate about their opt outs, it’s usually because there is more than two vegetables they don’t like, then that’s a bad sign. Some people ask to eliminate whole families of vegetables – ‘I don’t like greens,’ is a favourite. That means no kale, no chard, no spinach, no sorrel, no brussels sprout tops or turnip greens. It doesn’t go down well when I say, well, you can choose two of those.

And it goes on from there; after a month, about a quarter of our new customers cancel. My favourite recent story is a woman who rang up when she discovered us and was so excited to get a box. After her first one, she wrote us a lovely note about how beautiful our veg was and how she’d been telling all her neighbours about it. She didn’t opt out of anything. But then a couple of weeks in, she said that she didn’t like beetroot. Shortly after that she went to a bi-weekly box. Then she rang and said, could she not have onions as well, as she didn’t cook with them. Finally, she wrote an apologetic note, about six weeks in, cancelling her box, writing that the greens, which are almost always in our boxes, didn’t go with her ‘baked-fish diet’ and she couldn’t get any of her family to eat anything from the box. I despaired!

The question I have about all this, is how did we get to this extraordinary place where people don’t like much of the extraordinary array of vegetables that are grown in the UK? To even consider joining a vegetable box scheme, you have to, at least think that you like a lot of vegetables; so what’s going on with people who would never dream of joining a box scheme? Are they eating any vegetables at all, let alone local and seasonal vegetables? When you stand in line at the supermarket and look at what other people are buying, more often than not, fresh vegetables are a rarity.

Now I am a vegetable zealot, which you would expect, as my partner and I run an organic veg farm. I apologise for being unsympathetic to those not as enamoured as I with this staple food category, and I apologise also if what I’m about to say sounds self-righteous. Not liking your food is a luxury of the developed world. We have so much abundant choice of what to eat, that we can dislike and choose not to eat a lot of what is produced in this country. That’s a form of waste. We don’t think of it as wasteful, but it is. If we’re choosing not to eat our regional produce, than we’re probably eating someone’s else’s regional produce, which begs the question, what are they then eating?

One of my best friends is a picky eater. Pretty much the only vegetables that she and her daughters eat are green beans and salad. There is a theory about picky eaters – that their taste buds are underdeveloped and thus more sensitive to flavours and textures. But even picky eaters learn to eat new things. It’s a process of trying out new foods and building a taste for them, rather than just rejecting foods outright. We say ‘I don’t like that,’ because we can. If it were one of only a handful of things to eat, trust me, we’d develop a taste for it.

Chef Dan Barber did a great piece on how a delicious array of edible crops are wasted because they’re not thought of as food – these are the green manures that many farmers grow to nourish their soils. There is ‘a whole class of humbler crops,’ that are overlooked as a food source, including cowpeas and many mustards, which in fact could be eaten.

So how do we rectify this situation and why should we? We should because waste is a huge issue in how we eat, evidenced by the often cited statistic that a third of the world goes hungry, while the rest of the world throws away a third of their food. We have a moral obligation to waste less or their hunger is on our shoulders. But we should also learn to eat more widely because climate change is going to transform the range and availability of our food supply as we move deeper into the century, so better start now to learn to like a whole lot more than we do.

For starters, we need to make a commitment to our regional produce. Try a celeriac; try it again. Experiment with it – make a mash out of it, try it in soup, bake it with cream, cheese and beets (ooo, that’s going out on limb!) And when your child says, ‘I don’t like that,’ say ‘Yes, you do. You loved it the last time I gave it to you. Try it.’ (In my book, lying is acceptable in this situation.) When I tried this with my young daughter, she tasted it and said, ‘Yummy!’ You won’t always get a win, but persevere and I bet you’ll have a pay-off. When we all learn to eat more widely, there will more to go around for all of us and we’ll be healthier for it.”

Origin Green


An interesting Irish programme around sustainable food…

“The Origin Green promise is an unprecedented one. It is the only sustainability programme in the world that operates on a national scale, uniting government, the private sector and food producers through Bord Bia, the Irish Food Board.”

Website here.