## 2 Materials and Methods  
The field trial was established in the northeast of Munich at the organic trial site of the agricultural research center of the Technical University of Munich near Freising-Weihenstephan (48.39742 N, 11.64324 E) as a long-term experiment in autumn 2017. The experiment on different organic fertilizers was established as part of the ProBio Project (Project title: Optimum production and agronomic use of compost from organic and green waste in organic farming, www.projekt-probio.de, accessed on 20 December 2022). The soil is a silty and sandy loam with good supply of nutrients for grain production. The average values from 2017 until 2021 at this location were 914.4 mm of precipitation with an average temperature of 9.4 \({}^{\circ}\)C. Figure 1 shows an overview of the average monthly precipitation and temperatures at the research location. In 2021 after sowing corn by the end of April for the growth of the corn plants in the months from May to August, the precipitation was higher than the mean value shown in Figure 1. In May the precipitation was, with 156 mm, nearly 60 mm above the mean value. The same could be observed for June with 140 mm of precipitation and, thus, being approximately 60 mm above the mean value. For July 2021, the precipitation was approximately 135 mm and within the mean values. In August 2021, there was 171 mm precipitation, which was 15 mm higher than the mean value. In 2021 for the recorded temperatures, May had an average temperature of 10 \({}^{\circ}\)C, which was approximately 2 \({}^{\circ}\)C colder than the mean values from 2017 to 2021. Whilst May 2021 was too cold, June 2021 was, with an average of 20 \({}^{\circ}\)C, approximately 1 \({}^{\circ}\)C too hot. July and August were, with recorded temperatures of 18 \({}^{\circ}\)C and 17 \({}^{\circ}\)C, respectively, within the mean values. Before the experiment was established, soil samples were taken on all plots in order to record the initial humus and nutrient levels. For the compost trial, a fully randomized latin square design was used with four replicates. One plot was used for sensor measurements and harvesting, whilst the other was for biomass sampling at different growth stages. Each plot was 10 m long and 3 m wide, and in 2021 each plot consisted of four rows of corn. The row width was 75 cm and the plant density was 10 plants per m\({}^{2}\). In the observation period, in early April 2021, before planting the corn and depending on their N content, seven different organic compost fertilizers were applied, along with an unfertilized control. Five of them had two different N rates of 120 kg N ha\({}^{-1}\) and 240 kg N ha\({}^{-1}\). The application rate and nutrient content of the different compos  
Figure 1: Average precipitation and temperature at research location (2017–2021). given in Table 1. The fertilization was conducted according to the German fertilizer ordinance in one application for three years. The composets we used were from organic farmers (biogas fermentation residues, matured farmyard manure and the microbial carbonized compost). The organic waste composets, as well as the green composets, came from compost producers. These producers are certified according to RAL (Deutsches Institut fur Gottesicherung und Kennzeichung e.V., Bonn, Germany). The complete process of composeting consists of three phases. The first is the mesophilic phase with moderate temperature. It lasts only a couple of days. The second is the thermophilic phase with high temperatures up to 70 \({}^{\circ}\)C. This phase lasts between a few days to several months. Finally, the third phase is the maturation of the compost, which can last several months [50]. Unlike matured compost, fresh compost is gathered after the end of the mesophilic phase and just before the thermophilic phase has begun. The microbial carbonized compost is a special case.