Fecha de publicación: 29/04/2020 Fuente: WIPO "propolis" The present invention falls within the field of weeding systems, in particular steam weeding systems. In particular, the invention relates to an additive liquid composition which comprises the following agents: mix of citrus fruits, sugar, propolis, wax, honey and water dosed, mixed and treated with a raw fermentation artisan process, such as to obtain a fruit vinegar, in particular a citrus vinegar.