A Hamilton-based soil scientist is urging farmers to be wary of what he describes as a plague of questionable new fertiliser products that have appeared on the New Zealand market.
Dr Doug Edmeades says alarmism is used to create a market for the products, including humates, soil bio-stimulants, ground serpentine and basalt rocks, and a range of products from the sea.
He says farmers are told their previous practices such as using chemical fertilisers has destroyed the soil, which he says is not true according to soil surveys.
Dr Edmeades says the products won't do any good, and urges farmers to seek professional advice before spending their money.
He says something like the Fertiliser Act needs to be brought back, to provide assurance for farmers that what they're getting is useful and economic.