"Even products marketed as ‘organic’ may be toxic, say campaigners, with risks for the wider ecosystem".
"Gardeners are inadvertently killing scores of earthworms with soil conditioners marketed as “organic”, experts fear, as they call for tighter regulation on products that poison the invertebrates.
Earthworms may appear humble, but Charles Darwin thought their work in improving soil structure and fertility was so important he devoted his final book to them and said: “It may be doubted if there are any other animals which have played such an important part in the history of the world as these lowly organised creatures.”
However, some gardeners who want a tidy lawn remove worm casts, which can be viewed as unsightly, particularly if the casts – made of the worms’ excrement – are squashed and spread over the surface.
Dozens of products available to gardeners and greenkeepers say they combat these casts, reducing the time-consuming task of their manual removal. However, most contain saponins, which have been found to be highly toxic to earthworms. Some of these are marketed as “organic soil conditioner” with no mention of the deadly effect they have on worms. Others promise to “irritate and deter” worms, pushing them to deeper soil – not mentioning the active ingredient that could kill them."
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