Contaminated Manure & Fertilisers

I get quite a few emails with questions. I do try to answer most of them but there are times when I can’t cope. Generally the forums are good port of call, there’s usually someone who knows the answer on there. It’s no use asking me about fixing rotovators, for example. I’m a mechanical idiot but we’ve real experts on the forum.

This email, from John in Sussex, raises an issue I thought worth giving general publicity to. He says:

I took on an allotment 2 years ago (Feb.08) and the plot was completely covered with close grass plus an abundance of weeds; doc, dandelion, clover, couch grass, thistle and bine weed to name but a few. During the first year I dug half the plot by double digging but did not use any manure. I managed to plant 3 rows of potatoes and a row of runner beans the first season using only Growmore as a general fertilizer. The second season I planted 4 rows of potatoes, a row of runner beans and broad beans plus a few carrots, radishes, carrots and beet root. I am about to finish digging over the first half in readiness for the new growing season, then I shall start on the second half of my plot using the double digging method.

When I first started digging my plot I decided not to use manure due to the scare stories I’d read about chemicals fed to the animals finding their way in to the manure thereby rendering the soil contaminated for several years.

My question is; when I’m digging the second half of my plot should I use manure? If yes, is it safe to purchase a load of manure now then use immediately? If the answer to both is no, then what fertilizer, or fertilizers, would you recommend me to use?

The scare stories on manure are sadly not a scare, they’re true. The chemical aminopyralid is a very effective selective herbicide designed for grass that passes into animal urine and contaminates the manure. In effect it turns your manure into weedkiller.

The chemical was banned for a short while but has been approved again by DEFRA following promises from the manufacturer to ensure farmers are aware of the risks.

Any manure laid down in the last couple of years is suspect and will remain so until 2013. So if you import manure to your plot you need to check the supplier is aware of the problem and hasn’t used or had used by contractors the chemical.

If you can’t guarantee the safety of your manure, then your best bet is to use home made compost and green manures for the organic matter. To ensure sufficient nutrients, use a general purpose fertiliser like Blood, Fish & Bone or Growmore.

If you have a soil test kit, then you can check the nutrient levels and pH of your soil and apply straight fertilisers and lime in the exact proportions required to balance your soil.

There’s more information on the site – these articles should help you understand.

For fertilisers, there’s a series of articles here: Fertiliser and don’t miss Garden Lime.


Posted in Allotment Garden Diary
5 comments on “Contaminated Manure & Fertilisers
  1. Michele says:

    I have just come back from doing one of my daily jobs which is clearing the paddock which my daughters pony lives in of droppings. These are ususally put on the muck heap. Some are sacked up and given to my brother in law for his veg. garden. My point is, horses and ponies aren’t given the same sort of chemicals as farm animals and most people I know would be delighted for someone to take away some of the by-products produced by their four-legged friends. In particular, did you know that larger stables etc often have to pay someone to come and take it away? Maybe a group of allotment growers could help out some local horse-owners in this way, perhaps in return for a few carrots! Definately worth asking.

  2. John says:

    Hi Michele – you seem to have missed the point of my warning. If the paddock has been treated, often by a contractor, with selective herbicide containing aminopyralid, this is bound to the lignin in the grass.
    When the pony or horse digests the grass, it releases the aminopyralid which is excreted in the urine and thereby contaminates the manure.
    So unless the stable can guarantee the horses haven’t grazed on treated grass, then you need to test for contamination prior to using.
    It’s not a ‘blame’ thing, many stable owners had no idea what had been used on their paddocks.

  3. wendy wilson says:

    Hi I have just finished the backbreaking and very expensive job of tackling my new allotment and Guess what broad beans stunted and deformed climbing beans just going yellow and dying peas not looking right as a newbie It took a while for the penny to drop but I guess aminopyralid is to blame weather through the bought in compost or through the small amounts of manure or the hay mulch I am gutted and as the full time carer for my two disabled grandchildren who the organic fresh veggies were destined for What now all that work and time and money I am truly gutted

  4. geoff church says:

    Thank you Dow “AgroScience”. My allotment is ruined, my front garden is ruined and the vegetable plot in my back garden is ruined. Yes, manure contaminated with your product (aminopyralid) is still around in May 2011 and it’s still wrecking peoples’ hard work. You would not get away with this in the USA – you would be facing a class action lawsuit, with the prospect of forking out huge sums of money in compensation – and I think it should happen here in England.
    A few months ago I spent some days getting what I thought was really nice well-rotted manure from a well-run local stables (over 50 sacks of the stuff). It was spread liberally over the allotment that my wife has been working so hard on, and on our new front garden, in preparation for planting – and all over our vegetable plot in the back garden.
    The allotment potatoes came up – but they looked diseased. Last night I googled it and guess what I have found!…. Yes, Dow ‘AgroScience’, your product is in my manure and therefore throughout my land.
    Potatoes are not the only things to have been affected. Many other plants have either died, or not come up, or are just sitting weakly in the ground.
    Having read other posts, I cannot eat any crop I have grown, for fear of the consequences. ‘Dow’ says that their herbicide is pretty harmless to humans, but how can I TRUST a company that put this poison on the market in the way it did? It’s not hard to see that if you allow AMINOPYRALID into horse pastures, or into fields that will be used for straw for horse bedding IT WILL GET INTO HORSE MANURE. If it gets into horse manure, inevitably it gets into allotments and gardens.
    So, either Dow ‘AgroScience’ didn’t do their research properly (or even their basic thinking), in which case they are responsible, or they put the product onto the market KNOWING what the consequences would be, in which case they are also responsible. Either way, Dow ‘AgroScience’ – YOU ARE RESPONSIBLE.
    I feel that this company should be taken to court to compensate all the people whose hard work it has ruined. What does anyone else think?

  5. John says:

    Geoff – and everyone else – I totally understand your upset and anger. The fact is that this is a licensed product – thank you DEFRA. DOW have obeyed the law. Geoff is right that there would be lots of litigation in the states (and rich lawyers) but sadly DOW have followed the rules here in the UK.
    DEFRA has, in my opinion, become an organisation that benefits the big companies, the big farmers and not the public or the environment.

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