Extract from a by-product from production of sugar from sugar beet, sugar beet extract (SBE), can give rise to further opportunities in the prevention of diseases and better growth in the potato plant. The aim is to develop a plant-enhancing product that can be used to reduce disease attacks mainly in potatoes. The product may be of importance to both growers and consumers of potatoes, but in future also berries and ornamental plants. Even in the sugar beet industry and the forest tree nursery sector there are large volumes of cultivation, where SBE can be used. The product increases the ability to produce and consume healthy products that do not need or require less fungicides.