Posted: 01/10/2013 at 15:00
First post and rather a drastic statement I suppose. This has not been arrived at overnight.
Several years ago when council run composting sites started to spring up and the lobby for peat free compost was underway I read an article about the effect of hebicides within the composting process in the USA.
Green waste which is composted in huge piles, usually within sheds at elevated temperatures could be made available for use within several weeks by these super composting sites. It didn't and still does not seem right that nature takes several months to effectively break down compost for gardeners, but this process does it in days.
One problem they were experiencing in the process, was that gardeners green waste, lawn clippings etc that had been treated with weed and feed during the growing season was having an adverse affect on germination of seedlings grown in this compost. The other problem was that when the compost was used as a mulch it appeared to stunt the growth of established plants.
I bet anyone who reads this can associate with what I am saying!
It was discovered that the active ingrediant Clopyralid used in garden herbisides, while killing the lawn weeds, was found to be active for several years in the municipal compost. That is several years in your soil, for the clopyralid to break down to an acceptable level, where seed germination and stunted growth from mulching stopped being affected.
This problem replicated itself in the UK, as many gardeners started to use reduced peat compost.
At the time my concern was how this compost was being tested and what was classed as an acceptable quality standard. I obtained a quality manual from one of the North West sites, which informed the quality manager to plant several Tomato seedlings in a batch of compost that had completed the composting process. If they germinated then the compost was acceptable. However, no one had carried out any tests on the fruit produced from these seeds. Today several universities in Europe have carried out tests on fruit grown in this type of compost, and passed it fit for consumption??
All this seems fine, however all the results depend upon where the compost sample was taken from within the pile and testing showed that there were variances throught the mix. There was also another problem, that of heavy metals within compost. Heavy mentals when absorbed can be fatal in the long term.Today batch samples are sent off to labs for testing.
I have contacted over the years the soil association, the RHS, and most recently my MP, to try to obtain some form of certainty that this type of municipal compost is safe, both to use and to eat the resulting fruit.
A letter from,'The Secretary for Rural affairs', outlines the chemicals regulations directorate for the controls of pesticides. Saying that studies carried out would have been carried out to determin the safety of the products. It also states that composted waste must achieve BSI PAS100 before it can be used as a growing aid.
Now all this is well and good, however at Harrogate show this year the RHS person I spoke to, asking,'If all the problems relating to composted waste had,'Gone Away?' he told me.'Far from it' growers were up in arms because they couldn't get consistent germination from reduced peat products. You can immagine the problem trying to deliver several thousand Pansy plants to Tesco when only 30% had germinated!
I have also been imformed that a new study has shown that the ammount of peat in the world today was not declining as we have been lead to believe.
If you have lasted this long reading this post I am amazed!!!