During the growth season of 2019, Inagro tested recycling-derived fertilisers (RDFs) at its field trial in maize in Wingene, Flanders. This year, the field trial continues in spinach. Once again, five RDFs (ammonium nitrate, ammonium sulphate, digestate from co-digestion of pig manure, liquid fraction of separated digestate and pig urine) are being compared with the use of mineral fertiliser CAN, pig manure and a blank treatment.
Second year of field trials in Flanders, Belgium
With this field trial, Inagro wants to look at the short term nitrogen effects of the RDFs. The main goals of the trial is to establish a clear relationship between the amount of nitrogen applied by an RDF and the dry matter production that is reached for each applied RDF. For this purpose, each RDF is applied in four doses: the optimal advised dose of fertilisation (151 kg N/ha), - 30%, - 60% and – 100%. By calculating the apparent nitrogen recovery and nitrogen fertiliser replacement value, it will become clear which RDFs approach the fertiliser efficiency of mineral nitrogen fertiliser the most and have thus a high potential of replacing mineral fertilisers.
Results from the field trial in maize from 2019 were heavily influenced by the dry and hot weather. Results from this year in spinach will therefore be very interesting to analyse. Around the 1st of April, the field has been fertilised with Inagro’s very own specialised fertiliser machine. As soon as the frost stops occurring at night, the spinach will be sown sometime around Easter. After harvest at the end of May, samples will be analysed and these results will be compared with those of the first year.