Gavin backed Westland's 80% peat multipurpose compost in 2006.

But this March he appears in a campaign video demonstrating peat-free at garden centres. Defra says when consumers buy compost they should go peat-free and "play their part in the fight against climate change".

Gavin says in the campaign: "Consumers' concern about what they can personally do to help protect the environment is at a record high. Using peat-free products in the home and garden is one of the simplest, yet most effective ways that people can make a positive environmental impact and reduce their carbon footprint." 

Defra said: "Diarmuid refused to support campaigns with Westland for a number of years despite being asked on an annual basis. He continually stated his peat-free ethos to them and eventually as a result of this they developed a reduced peat option, West+, the first mass-market reduced-peat product. As a pragmatist, he felt this was a major step in the right direction and was delighted to have influenced their production in such a way."

A Westland representative said: "Westland Horticulture has enjoyed an excellent working relationship with Diarmuid and his help and advice continues to be very valuable. Our first totally peat-free compost was launched in the early 1990s.   Jamie Robinson, our technical director, started work on the West+ programme in 2000 and following extensive research and trials, was launched in 2005. As one of the UK's leading producers of domestic garden composts the development of West+ has helped us exceed consumer performance expectations while also to reducing our peat use by more than 60%. As a result all of our products are now either peat-reduced or totally peat-free."

Meanwhile, garden centre representatives have reacted to Defra not wanting them to sell peat from 2020.

Hillier managing director Andy McIndoe said: "Lots of work has been done on reducing amount of peat in composts with good results, but they are not always perfect. I am all for reduction in the use of peat providing the full environmental impact of the alternatives is always considered — for example energy used in manufacture and fuel used in transport."

Squires managing director Dennis Espley said: "If this is going to be legislation we will comply with it. Obviously our concern is that there will be composts with comparable performance to give our customers a successful result."

Glendoick director Ken Cox said: "I will set up a peat shrine in my garden centre with evidence against not using it and to say the Government is talking rubbish. This is not an issue in the rest of the world — when will the British Government admit it is wrong."

Phil Douty, Dobbies sales and marketing director said: "We are cognisant of the Defra phase-out of peat-based compost campaign and Dobbies has made a strong start with the introduction of peat-free composts in all of our stores — we are on track to meet the government's targets and we exceeded our internal targets for the last financial year. 

"We encourage consumers to purchase peat-free at point-of-sale, we have introduced a Dobbies own-brand of peat-free compost and importantly, we educate consumers on new ways of thinking about how they manage their gardens from an eco perspective.  Dobbies' overall environmental vision which aims to continually raise the practice of energy conservation, sustainable sourcing and recycling across the business places us at the forefront of sustainable retailing."

Garden & Leisure said: "The Garden & Leisure Group, which won Best Environmental Policy Award at the Garden Retail Awards 2009 are pleased to support any Government initiatives which demonstrate best practice on green issues.

"The Group has already made considerable steps towards reducing its peat sales and educating customers about the adverse effects of peat on the environment in line with its strong environmental policies.

"In 2010 year to date Garden & Leisure Group has seen a 17% reduction in ratio of peat sales and they were previously running 10% below the industry standard.

"Educating amateur gardeners about peat is high on the group's agenda, and they have been actively promoting Earth Matters in flyers since February with current sales standing at over 1,000 bags at 2 for £10 in a 3-week sales window.

"There is also a strong buy-one-get-one-free promotion on Westland John Innes compost in the Group's March flyer, which began on 8th March.  WRAP are also keen to collaborate with the group about activities promoting peat free sales. Some of the Group's stores are running ‘Let's Get Growing' sessions with the public, which will also help to inform and educate amateur growers about peat-free alternatives."

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