Important! Please read this post if you are growing vegetables, some bagged composts contain manure.
Most of you probably know about this – gardeners all over the UK have been affected by using manure contaminated with industrial weed-killer. It is not just people who have used manure on their gardens and allotments, some bags of compost bought from garden centres contain manure too.
The herbicide Aminopyralid is manufactured by Dow AgroSciences, for the control of ‘injurious’ weeds such as docks, thistles and nettles and it appears that residues of it have turned up in manure. Animals eating grass treated with the product excrete it in their manure as it travels through the body without breaking down, it seems that residues of aminopyralid may last several years in manure heaps. The product has a label warning farmers not to sell manure that may have residues in it. It is not licensed for use on food crops although some farmers might have used it if they did not read or ignored the small print.
Dow AgroSciences state:
It has long been known that it is possible for low levels of product to be found in manure and that the use of such manure as a fertiliser or compost may, in some circumstances, cause damage to sensitive crops.
Call me suspicious if you like but if this product is excreted in manure is it stored in the bodies of food animals or finding its way into milk?
If you have problems and don’t use manure or products containing it but use a lawn weed killer and compost your clipings or use them as a mulch that could be causing it. Clopyralid a lawn weed killer is a similar product which does leave a reside in compost. It has been de-registered for lawn use in the USA since 1999. It is still available for sale in the UK as a lawn weed killer in products such as ‘Verdone Extra’ made by Levington, there are probably others. It is also in products that are used on public grass and playing fields, treated grass may well end up in council made and sold compost.
In this insane world that we live in anyone can legally use products like Aminopyralid or Clopyralid but it is illegal for gardeners to make or use their own tried and tested fungicide from horsetail or insecticide from rhubarb leaves. Personally I think that whoever decides products like this deserve a licence should be strung up.
A lot of people, experienced gardeners and others growing this year for the first time are not only doing so because home-grown veg tastes better but so they may not have to make the stark choice during the winter of heating or eating. So not only have plants, time, effort and money been lost due to an ‘approved’ herbicide, all the crops from those plants have been lost as well!
If you have been affected by this it may still be possible for you to get a crop by growing in containers as there are still some seeds that you can sow see Vegetables to Sow in July, you could also get some autumn and winter potatoes by Growing Potatoes in Bin Bag.
Which plants are affected?
Mainly potatoes, tomatoes, beans, peas, but also other vegetable and salad crops. Some ornamental plants including roses.
What to look for?
RHS say typical symptoms include cupped leaves and fern-like growth on sensitive plants. The shoot tips become pale, narrow and distorted, with prominent veining on the foliage. Growth generally is stunted, leaving most crops unusable.
There are some photos of damage on the RHS site, click on the link above.
Can I eat the affected crops?
Dow AgroSciences (the manufacturer of the herbicide) state: If you are concerned about damage to your crops, or that any manure used on your food crops may have contained residues from products not designed for use on food crops, in our view it would be prudent not to harvest the crop and wait till next year before replanting in the affected area.
Any unused manure should be returned to the supplier so that it can be spread on land not used for food crops, it does not break down very well if stacked in heaps.
Read more about the problem via these links:
‘Home-grown veg ruined by toxic fertiliser’ in the Guardian.
Loads of people have comented on this post ‘Aminopyralid Herbicide Residue in Manure Killing Crops‘ on allotment.org, including someone who had bought organic compost that contained manure.