Grape pomace biofertilizer enhances edible calendula cultivation

Researchers from the University of Campinas (Unicamp) and the Federal University of Paraná (UFPR) have developed a biofertilizer using grape pomace to enhance the cultivation of edible calendula flowers. The study, published in ACS Omega, utilizes digestate—a liquid biofertilizer produced through anaerobic digestion of grape pomace, a byproduct of the wine industry that accounts for 20% to 25% of processed grape mass.

The application of this biofertilizer significantly improves the nutritional and antioxidant profile of the plants. During summer testing, the use of the digestate resulted in a betacarotene increase of over 250% compared to conventional cultivation methods. In winter, the treatment helped maintain mineral levels and pigment retention. This innovation offers a sustainable method for the food and cosmetic industries to produce high-value edible flowers while repurposing winery waste.