For Phythopthora infestans control it is recommended to choose open sides, with row width of 0,75 m and to avoid areas with high humidity. Pregermination will ensure a growth advantage of about 2 weeks. This can produce additional yields of 10 – 20% compared to cost of 90 – 140€/ha and year. Different varieties should be cultivated using the vertical resistance at the same time to reduce the overall risk. Copper products are the most promising alternative (cost efficient; postponed infestation; increasing yield up to 20%) to fungicides in organic farming. Copper products are preventive measures and used before first signs of infestation, a better control using low dosage in short intervals is achieved, small reductions of infestation increase yield about 10 – 20%, only be used under conditions of optimal nutrient supply. In warm humid weather conditions weekly spraying, in dry conditions less often (dosages of 300 – 500 g/ha copper).
