The initiative is a collaboration between Cardiff Farmers Markets, Food Cardiff, and a group of organic growers, social enterprises and community organisations.
The Planet Card will hold a value of up to £11 per week and using it holders will be able to switch from regular fruit and vegetables to organically produced versions, without being left out of pocket.
The card can be used at a number of organic fruit and vegetable stalls at any of the Cardiff Farmers Markets across the city.
The pilot has an initial group of 20 shoppers, with a second, follow-up phase planned with 120in the summer. The evidence from both phases will be used to support proposals for changes to food policy at a local and national level.
The scheme has been made possible by Bridging the Gap, an initiative established to tackle the matter of food that is good for both health and the planet, often coming at a higher cost than less healthy and/or planet-friendly alternatives.
Bridging the Gap is a partnership between Sustain, Growing Communities, the Alexandra Rose Charity, Nourish NI, Nourish Scotland and Food Sense Wales.