The field trial was set up with 5 blocks along the slope gradient each containing a control and three substrate treatments(see Appendix Fig. A1). Each plot included four grape vine rows and three inter-rows, respectively. The three substrate treatments were: biochar alone (referred to hereafter as ‘biochar’), compost alone (‘compost’) and compost produced together with initially 20 vol% biochar, i.e. the biochar was already present during the composting process (‘bc-compost’)
All substrates wereapplied on June 8th, 2011 at the beginning of the main growthperiod of the vines. After the spreading of the different substratesby hand onto the soil surface (vine rows included), the soil wassuperficially tilled in the inter-rows with a tiller to 7–10 cm depth.One day after application and tillage, the green cover mix was sownon the entire surface (vine rows included) by hand (1.5 g m−2). Theseeds germinated 10 days later.