Fairtrade suppliers will be given a discount to show off their wares on national TV as Channel 4 plans to dedicate an entire ad break to the cause.

The themed ad break will run in support of Fairtrade Fortnight and the Fairtrade Foundation's The Big Swap campaign, which kick off on 22 February.

The break itself will be broadcast on 25 February during the final episode of My Dream Farm, a new series presented by Monty Don following six families who have given up the rat race to take up farming.

The broadcaster said it was the perfect programme to use because of its emphasis on small producers using sustainable farming methods and backyard animal husbandry to generate food production.

Before the adverts run, the channel's ident will appear accompanied by a voiceover informing viewers that they are about to see "something special".

"We are always looking at ways to make the TV ad break more interesting and appealing, and our themed ad breaks have proved to be hugely popular with viewers and advertisers alike," said head of strategic sales at Channel 4 Mike Parker. "The Big Swap is a brilliant initiative and we are keen to help support it, so we are asking brands that have a Fairtrade product to come and talk to us and get involved."

Channel 4 hopes to entice smaller suppliers who have not been able to afford TV advertising before by offering a production subsidy for new advertisers.

The Big Swap aims to persuade shoppers to swap their usual groceries for Fairtrade alternatives. It hopes to oversee "one million and one" swaps over the two weeks.

"Fairtrade Fortnight is a fantastic opportunity for retailers and companies to promote Fairtrade, improve product visibility at point of sale and give customers access to more Fairtrade items," said Fairtrade Foundation executive director Harriet Lamb. "Customers consistently tell us that they would buy more Fairtrade goods if they were available, so we know the market exists."