Fairweather's Compost Tea is brewed in a garden shed on site and has until now not been sold to the public. Garden centre owner Patrick Fairweather said it offered a "holistic approach to gardening with the benefit of cutting harmful chemical use".
The nursery adopted the product for commercially growing garden plants from Dutch nurseries in 2001 and since then has halved the amount of chemicals used in growing crops.
Fairweather said: "Compost Tea can benefit fruit, vegetables, flowering plants and even lawns, and one of the most important benefits is a reduction in their exposure to potentially harmful chemicals."
The tea, which is to be sold in recycled milk bottles, is naturally produced when compost breaks down into plant food.
The brew's basic ingredients are dried foliage, molasses, kelp, carbon, organic soil compost and fish extract.
It micro-feeds plants by providing nutrition naturally, which helps plants to resist and suppress pests and diseases more efficiently.