**Appendix A**

**Figure A1.** Climate chart of the experimental location Ettlingen (ET) for 2018 (**a**) and 2019 (**b**). The monthly cumulative sum of precipitation (mm, blue bars), the average air temperature (◦C, solid, red line), the mean long-term annual precipitation (mm, filled, green diamonds), and the average long-term air temperature (◦C, dashed, orange line). (Data source: Meteorological station Rüppur, 3.5 km linear distance to experimental site).

**Figure A2.** Climate chart of the experimental location Tachenhausen (TH) for 2018 (**a**) and 2019 (**b**). The monthly cumulative sum of precipitation (mm, blue bars), the average air temperature (◦C, solid, red line), the mean long-term annual precipitation (mm, filled, green diamonds), and the average long-term air temperature (◦C, dashed, orange line). (Data source: meteorological station Tachenhausen, 0.5 km linear distance to experimental site).

**Figure A3.** Climate chart of the experimental location Forchheim am Kaiserstuhl (FAK) for 2018 (**a**) and 2019 (**b**). The monthly cumulative sum of precipitation (mm, blue bars), the average air temperature (◦C, solid, red line), the mean long-term annual precipitation (mm, filled, green diamonds), and the average long-term air temperature (◦C, dashed, orange line). (Data source: meteorological station Herbolzheim, 9.3 km linear distance to experimental site).

**Table A1.** CP (crude protein), CL (crude fat), CX (crude fiber), CA (crude ash), NfE (nitrogen-free extracts) content (% of DM), biogas and methane yield (L kg−<sup>1</sup> oDMC) and GE (gross energy), ME (metabolizable energy), and NEL (net energy for lactation) (MJ kg−<sup>1</sup> DM) for the different N-Levels and seed placement of the intercropped flowering partners (IFP) in ET 2018.


Values with the same letter within one parameter indicate non-significant differences within the three factor levels (N-Level and Seed placement) (HSD-test, α = 5%). \*\*\* *p* ≤ 0.001, \*\* *p* ≤ 0.01, \* *p* ≤ 0.05.
