Congo grass is a summer growing species yielding high amounts of biomass under high N supply. DM yield could exceed 20 t/ha in Australia and South America, and up to 25 t DM/ha in Sri Lanka under 366 kg N/ha fertilizer (Husson et al., 2008; Cook et al., 2005). In low fertile soils of Coronel Pacheco (Brazil) with no N fertilizer, Congo grass yielded only 6 t DM/ha. The biomass production could be up to 12 t DM/ha after 150 kg N fertilizer application (Cook et al., 2005). Biomass production is at its highest level during the second year of establishment. Congo grass is markedly less productive than signal grass, which reduces its potential as a forage crop, particularly in low-fertile soils (Schultze-Kraft et al., 1992).
Congo grass can be propagated both from root stock and from seeds (Urio et al., 1988). If propagation by seeds is intended, the dormancy of seeds will be stopped after 6 months storage after harvest or by chemical scarification. Seeds can be broadcast on a well-prepared seedbed and should not be buried deeper than 2 cm. Congo grass seedling vigour is high and prevents weed development (Husson et al., 2008). If Congo grass is vegetatively propagated, stem cuttings with rooting nodes are necessary. As Congo grass requires good soil fertility, it is important to provide N, P and K fertilizers prior to planting and during growth (Cook et al., 2005). Once it is established, and provided it receives enough N fertilizer, Congo grass spreads readily. Congo grass flowers later than signal grass (Schultze-Kraft et al., 1992). It should be cut before first flowering and then at six week intervals (ILRI, 2013). When grazed, Congo grass moderately withstands heavy grazing (Cook et al., 2005).
Association with legumes
Congo grass can be grown in association with a wide range of legumes such as stylo (Stylosanthes guianensis), puero (Pueraria phaseoloides), greenleaf desmodium (Desmodium intortum), centro (Centrosema molle) and leucaena (Leucaena leucocephala). In association, Congo grass should be heavily grazed so that the sward becomes open and allows legumes to establish and persist (Cook et al., 2005). When grown in association with stylo, both plants can be harvested together to make good quality silage (FAO, 2015). It is possible to make pure Congo grass silage with formic acid, and best quality was obtained with 2 L formic acid/t (Lowilai et al., 2002).