On most organic dairy farms (also farms with goats) the ration is based on grass-clover. There is a need for a better knowledge of its feeding value to better manage the quality of grass clover at one side and to incorporate it efficiently in the ration at the other. In contrast with grass and maize silage there didn‘t exist specific formulas to estimate the feeing value of grass clover silages until recently. Therefore, 7 batches of grass/white clover and 8 batches of grass/red clover were investigated in the course of 3 years. The botanical as well as the chemical composition was determined. Besides, the digestibility was determined with whether sheep to calculate the energy value and also the degradability in the rumen of canulated cows to derive the protein value. Finally, specific regression equations were developed to estimate the energy (NEl, FOM)and protein value (PDI, DPB) of grass clover silages based on lab parameters, which enables a relatively fast, accurate and cheap evaluation.