Alan Titchmarsh may be Britain's favourite gardener - but his compost isn't up to scratch, says Which?.
According to the Daily Mail, his Peat-Free Multi Purpose Compost came last in a review of 25 different varieties. After poor results when sowing seeds and raising young plants, Which? rated it as a Don't Buy.
Meanwhile, Bord na Móna UK's Growise Multipurpose peat-reduced and the company's B&Q Verve Sowing and Cutting both won 'best buy' awards.
Titchmarsh's compost, which is sold only through Waitrose, was launched last spring, with a 30-litre bag costing £3.50. The product came as some surprise, as Titchmarsh had been vocal in the past about the shortcomings of peat-free compost.
Four years ago, he was criticised by Friends of the Earth for arguing in Gardeners' World magazine that sometimes there was no alternative to peat - and this is the first peat-free product he's supported.
Titchmarsh told the Daily Mail that the Which? results were very different from his own experiences using the product, and that it was "the best peat-free mix I have ever used".
"That's why I was - and am - happy to put my name to it," he said. "Perhaps other gardeners are best advised to try it and make their own judgements."
As a result, compost that isn't labelled peat-free will usually contain at least 70% peat. But there's a big downside in terms of damage to the environment. Peat is sourced from lowland raised bogs, a habitat that's becoming rarer not just in the UK but across Europe too. Most of the peat found in British compost comes from Ireland, the Baltic States and Finland.
Because of these concerns, most manufacturers - including Bulrush, Gem, Godwins, J Arthur Bowers, Lakeland, Scotts and Westland - offer completely peat-free compost. Others offer compromise versions.
"Completely peat-free media are said to be the best choice for the environment, but product consistency can be problematic, so many brands also offer 'reduced-peat' choices, blending into the formulation up to 50 percent non-peat materials. Manufacturers are continuously improving the quality of the blends," says the Royal Horticultural Society.
"Preferably, choose peat-free compost with good on-label information. Read and follow the instructions on the packaging about the suitability of the mix for particular purposes."
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