/ Food & Drink

Organic food loses our taste test – surprised?

Colourful fruit and veg

Organic devotees look away. Which? Gardening’s latest research suggests that veg grown non-organically tastes better, has more nutrients and often has higher yields than organically grown equivalents.

Surprised? So were we. And we’d be the first to say that the results from this trial are not definitive – this was a small-scale trial, involving three types of veg – potato, tomato and broccoli (calabrese).

This isn’t the first time that organic food has come out poorly in research. In 2009 the Food Standards Agency published a report which claimed there were no significant benefits to be gained from eating organic. But of course, that was all about organic farming, and not about growing your own.

Health risks of pesticides

However, back in 1991 Which? Gardening was so concerned about pesticide residues on home-grown food that we carried out a trial. We grew carrots and lettuces and treated them with a wide range of garden chemicals up to their maximum limits.

Even back then we concluded that the residues left behind were within the limits laid down for commercial growing, and that they were unlikely to pose any health risks.

Is it worth gardening organically?

So where does this leave us? Like many people, I grow the food I eat organically, and that’s not going to change. I buy into the whole ethos of organic gardening and I accept that I’ll lose a few crops to pests or diseases, frustrating though it is.

I don’t want to douse my crops with chemicals, which for all I know could create a potentially harmful ‘chemical cocktail’.

What about you? Is gardening organically a waste of time and effort, and are you happy to use chemicals when necessary? Or should we all be learning to garden organically?

Sheena Fraser says:
24 February 2011

This was a flawed trial.
I will continue to buy organic. To me it does taste better. It is better for the soil, animals, wildlife and the environment. Compare soil that has been continually treated with pesticides to that gardened/farmed organically. Which is the living soil?

Sebastian says:
28 July 2011

You do realize that organic vegetables are still treated with pesticides, right?

They’re just different pesticides.

But NOT Glyphosate!

I agree with Mark Shaw the experiment was flawed.The benefits acheived from managing soil organically will last in the soil for years. The trial plots should have been non-organic, the plot chosen for organic should be given two years conversion (which is the rule for certified organic growers) before the experiment started . As for the tomatoes, the organic grow bags are not allowed to include peat a which is not allowed for sustainability reasons, but is an ideal growing medium so it not surprising the tomatoes in the non-organic bags were deemed better.

Hello, I’m the head of Which? Gardening research. It is important to remember that we’re looking at the experiences of the home gardener and what they can achieve.

As for the ‘organic’ growing bags, they were peat free. In previous Which? Gardening tests both the organic growing bags and tomato fertilisers have out performed the conventional ones on offer.

Geoff says:
24 February 2011

Are the full results including measures of statistical significance and confidence intervals available? Having read the report in my copy of Gardening Which this month I am disappointed by the unscientific reporting of an allegedly scientific investigation. Such comments as “Significantly higher anti-oxidant capacity” should be accompanied by a p value and 95% confidence intervals to clarify whether these are statistically or biologically significant (or both).

Which? never publish p values and 95% confidence intervals. We are confident that there is a significant difference between the two samples tested, and don’t feel the majority of readers want to read all the details of the trials.

Geoff says:
2 March 2011

Indeed, and that is unfortunate. Were medical journals to take the same attitude my ability to choose appropriate treatments for my patients would be severely compromised. Certainly not all people will want to read the full detail, but for those (like me) who have an open mind on these issues it makes it very difficult to know what to do with the information you have supplied (other than simply discard it as uninterpretable).

George Frasier says:
24 February 2011

Songbirds endangered, Hedgehogs endangered, Bee populations facing extinction – 2 species of bumlebee now extinct in UK, evidence of diminishing pollination in UK. The silent spring is here. And the voice of science replaced by small scale tests on 3 types of vegetable. Can ‘Which’ magazine tackle climate change next and allow us all to sleep a little better?

I think the point has been missed here, which is, does organic food taste better and is it nutritionally better for you when you grow it in your garden at home, compared to using conventional gardening methods.

Allan Chapman says:
14 May 2012

Contrary to George Frasier’s request, can Which? be more objective when considering man’s effect on climate change. I would like to see less bias in the light of the recent Climategate scandals.

Over the last couple of centuries, the use of artificial fertilizers and chemical pesticides has grown enormously and hardly been checked by the relatively small growth in organic food production. In this same time scale, so has human life expectancy. Is this not the ultimate answer to this problem, BUT only if one ignores the effect on other species.

Vic Shorrocks says:
25 February 2011

The Gardening Which trials set out to assess the crops for yield and quality, taste and nutritional value and to determine which growing method, organic of non-organic, came out on top. Nothing more.
Sadly the design of the trials did not allow any conclusions whatsoever to be drawn that could be extrapolated to your garden or mine. This was because they did not make sure that the amounts of nutrients supplied by the two methods were the same. Organic materials when added to the soil provide nutrients and can with some soils improve structure and water holding capacity. The results will be skewed according to the amounts of nutrients applied and interpretation made impossible.

For many years, at least up to the 1950s, the advocates of organic farming in the UK believed that the soil fungi which were intimately associated with crop roots via the fungal threads (hyphae), brought an unspecified health-promoting chemical or chemicals from the organic matter in the soil. The chemicals was supposed to enter the root then the shoots and seed and ultimately into the diet where, according to Balfour, there would be dramatic improvements in the health of the nation. They even believed, and said they had evidence, that animal diseases such as foot and mouth could be prevented if animals were fed on organically grown crops. It is possible that some believe this nonsense today.

Believers in the organic food and farming will continue to find a basis for their beliefs regardless of the evidence. I will address one such belief which is that eating organically grown crops means eating pesticide-free food.

This is not correct.

If you wish to ensure you consume the minimum amounts of hazardous pesticides (both natural and man-made) you are advised to eat vegetables and fruit crops (in fact all crops) that have been treated with synthetic pesticides.

This advice is the inevitable conclusion from the evidence that has been building up over the last 20 years on the quantities and properties of natural pesticides in plants.

All plants contain a formidable array of natural pesticides which protect them from pests and diseases. When a plant is attacked they produce more of their particular set of natural pesticides.

The concentrations of natural pesticides are much higher than those of synthetic pesticide residues. The result is that daily we consume about 1,500 mg of natural pesticides compared with 0.1 mg of synthetic pesticides.

Natural pesticides are just as hazardous as synthetic pesticides in that they have been found to be carcinogens, mutagens etc in rodent tests. As is the case with all chemicals, whether man-made or natural, 55% of natural pesticides are known to be hazardous when assessed by rodent toxicological tests.

It is therefore far more important to reduce the amount natural pesticides in the food you eat than that of synthetic pesticides if you want to restrict your intake of hazardous pesticides.

A crop that has not been treated with synthetic pesticides, as is the case in organic farming, is likely to contain more natural pesticides because any attack by a pest or disease will have stimulated the production of more natural pesticides. It is therefore preferable to eat food produced from crops that have been sprayed with synthetic pesticides.

Removing the pesticide-rich skin of a vegetable or fruit will reduce the amount of natural pesticides consumed.

It is estimated that there are thousands of natural pesticides in plants. It would be an enormous task to study them all but much more work is clearly required on the natural pesticides that are judged to be the most hazardous. At the moment it can be said that about 55% of the natural pesticides are hazardous. All crops contain hazardous natural pesticides and therefore all crops are potentially hazardous.

Finally all believers know that the Haughley experiment (concluded by the Soil Association) which lasted 30 years did not show any benefits of farming organically in terms of crop or animal production or health. Moreover when organic matter was used soil fertility fell.

It is important to remember this trial looked at the home gardener not at organic agriculture. Which? Gardening followed best practice for the home gardener on an identical plot of land in two regimes and compared the two. Quite simple, and like many scientific experiments, has raised more questions than answers, which over time I hope we’ll see addressed.

Stephen says:
25 February 2011

Organic production is seriously over rated. It often produces poor quality produce.
It is possible to use some non organic materials particularly fertilizer in moderate quantities without compromising quality

D. Hasleworth says:
25 February 2011

I am really appalled by this; the headline and summary are strong indeed and go well beyond the limited study that had actually been carried out in a completely unscientific method. Gardens are very different to agricultural land, but are increasingly becoming the last refuge for thousands of species ranging from soil microbes through to birds. As others have stated the ‘taste’ factor is simply irrelevant and against all real scientific study and I fully concur with the statements that this is a regressive and publicity grabbing exercise which do little more than further tarnish the reputation that ‘which’ once had.

It’s true this trial was flawed, but more importantly, the “conventional” approach to organics is flawed. Before you throw tomatoes at me, let me explain.

Conventional organics is can most succinctly be summed up into two principles. #1 is don’t use any “prohibited” materials, be they synthetic fertilizers, herbicides, or pesticides. #2 increase the organic matter in the soil using compost, mulch, cover crops etc…

The overriding idea behind organic gardening is a negative, as in what NOT to do. As Michael Astera of http://www.soilminerals.com outlines in his book “Ideal Soil”, what makes ANY produce, organic or conventional tasty or nutritious is minerals, plain and simple.

A plant does not care where the NPK comes from, whether the source is synthetic or “natural”. You do realize that most “synthetic” chemicals are natural don’t you?

So, here’s my proposal. #1 principle. Don’t put ANYTHING on or in the soil that will kill an earth worm. What this means is you can use synthetic NPK, but it has to be REALLY diluted or better yet, run through a biological break down process, such as composting or anaerobic digestion. #2, balance the soil mineral profile to eliminate the “limiting factor”, or the missing mineral that is holding the plants back from achieving their full genetic potential. #3, increase the life in the soil by employing the principles set forth in Natural Farming.

Then let’s compare the taste and nutrient density of conventional to beyond organic. THAT would be a fair test!

Please note, I am NOT an unbiased observer. I manufacture organic fertilizer with added major, minor and trace minerals that includes beneficial micro organisms to build soil life.

Boringsceptic says:
26 February 2011

I found this in the Wikipedia article about “Confirmation bias” :-

Ross, Lee; Anderson, Craig A. (1982), “Shortcomings in the attribution process: On the origins and maintenance of erroneous social assessments”, in Kahneman, Daniel; Slovic, Paul; Tversky, Amos, Judgment under uncertainty: Heuristics and biases, Cambridge University Press.

Ross & Anderson found that :-

“Beliefs can survive potent logical or empirical challenges. They can survive and even be bolstered by evidence that most uncommitted observers would agree logically demands some weakening of such beliefs. They can even survive the total destruction of their original evidential bases.”

So there …

JossCritchley says:
27 February 2011

This has been an intriguing read; there are many comments attempting to drag the emphasis of the debate into the realm that research and study is now concentrated on, which is not taste or even comparable prices – but the ecological angle. There has been no response to the comments raised in this regard asides from the thumbs down from some people – it would have been wonderful to read their thoughts as to why the ongoing demise of the British natural environment is a non issue or why they think it is otherwise.

With mounting evidence that any use of chemical products, (and as one person hinted at the overuse of organic products), affects the stability of all natural elements in both our rural and urban environments – in particular trees are showing signs of damage by way of too much nitrogen and other elements, which have offset our soils possibly well beyond a tipping point.

The UK is rapidly establishing itself as the ‘pseudo science’ capital of the world, with regards climate change and many other elements. The BBC regularly drag in any old right wing hack to counter peer reviewed scientific discovery and this is obviously seen as great entertainment. The Which trial, clearly flawed scientifically was at least a demonstration that many of us would adhere to ourselves if we had the time to discover our own opinion. The only problem was that this issue has long since moved on from this ‘debate’ in light of the damning evidence re our natural environment as a whole.

Are the British now at a stage where many will only listen to real facts with regards our natural environment and the crisis it is in, if it is relayed by way of the witticism of Jeremy Clarkson on our TV sets?

Ian Cheal says:
1 March 2011

I do not doubt that the tests were right however I was horrified to see headlines in the media that Organic grown food does not taste as good as Non Organic.
The fact is that everyone I know says what a huge difference my and other organic grown are compared with shop non organic veg.
Shop non organic veg and fruit are often grown under industrial methods, seeds to make quick results and picked before they are ripe and the outcome is a poor taste.
I am saddened that WHICH have not spelled out to the public that their test was just like for like trials and not the difference between end products in supermarkets and Organic Growers.

Which? Gardening has made it clear in every statement that we looked at organic and conventional food grown by methods that would be employed by the home-gardener – i.e. not in an agricultural setting.

Matthew says:
1 March 2011

Did you use the same varieties for organic and conventional systems? Was it the same soil types? Randomized replicated design in production? Same amount of water and other treatments?

Calling this “research” without showing your methodology does not cast a positive light on your organization. It’s like calling something a “survey” when all you did was ask a half-dozen friends the same question. Poor work, and disappointing considering your organizations status.

Yes and yes, and apart from the specific organic and conventional treatments we treated plants using good horticultural practice in order to maximise their yield. The methodology is outlined in the full report in the March issue of Which? Gardening

Sarah says:
2 March 2011

You still haven’t answered any questions about which plant varieties were used.

We used Which? Gardening best buy varieties:

Tomato ‘Gardener’s Delight’
Calabrese ‘Ironman’
Potato ‘Sarpo Axona’

The reason people buy organic food is usually to avoid consuming pesticides & GM, not taste.
The research is therefore spurious.
You cannot taste pesticides & GM but they still make you ill.

Ask people instead whether they would prefer to eat clean, naturally-produced food, or food laced with chemicals & genetically modified ingredients and whether such food should be labelled..

Organic is great local organic is even better. But local non organic is better than foreign or ‘travelled’ organic. Freshness is the most important thing, and getting the story of how the fruit and veg have been produced. Supporting your local farmers and the local economy is also very important. Which is why we set up Social Enterprise bigbarn.co.uk simply type in your post code to find your local producers.

Sandr Hansen says:
16 March 2011

wow, I think many people who’ve read this do not understand, this is a taste test for the HOME GARDENER. It makes sense to me. I don’t use any chemicals on my home garden for fear of killing beneficial bugs, butterflies, and such. But, I know if I was trying to grow tomatoes and my plants had blight so bad that the tomatoes couldn’t get enough nutrients from the plant itself, that if I did use something to combat bugs and disease, I could make a tastier more nutrient rich product. It depends on the season and what’s going around in bugworld, and fungus world. Our japanese beatles are so bad in the u.s lately that it’s almost worth considering toxic chemicals. How can something taste good if you can’t even grow the host plant sucessfully?

Boringsceptic says:
16 March 2011


Are “our japanese beatles” a really rubbish tribute band? No wonder they get sprayed with toxic chemicals.

Sandr Hansen says:
16 March 2011

@Boringscep, HA, Hilarious! Thanks for the morning laugh! oops, sorry about the typo! I adore the BEATLES not BEETLES:)

In a new Which? Gardening test, we found that organic slug pellets are just as good as non-organic ones. Though DIY methods, like egg-shells and beer traps, aren’t good alternatives. How do you get rid of your slugs? https://conversation.which.co.uk/energy-home/killing-slugs-organic-pellets-not-alternatives/

mike says:
29 March 2011

Looking back, perhaps this should have been titled ‘Home grown organic food loses our taste test – surprised?’. Its easy after the fact, eh?