Input of nutrients and pesticides
On average, over the three crop rotation periods, the organic systems received markedly lower amounts of the macro-elements N, P, and K. According to the experimental design the amount of organic matter applied was similar. In the bio-dynamic system, the input of potassium almost doubled in the third crop rotation.
period due to delivery of manure from a different farmer. The arable crops were treated with pesticides 3.6 times per year on average, whilst the organic plots were sprayed once every second year. The bio-dynamic plots were sprayed several times per year with preparations 500 and 501.
Up to 9 pesticide amendments were necessary in conventional potatoes due to the high incidence of pests and diseases. Direct control of late blight (Phytophtora infestans) was performed in the bio-organic system with copper sprays, and in both organic systems Bacillus thuringiensis preparations were used to fight the potato beetle.
The amount of nitrogen applied as nitrate or ammonia made up the biggest difference between the systems. Total N, P and K was 40–50 percent lower in the organic systems.
Fertilization and plant protection were performed according to the regulations of the farming systems under investigation.
Average input of nutrients in kg per hectare and year, K2 = 100 %
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