It is recommended to add 1500 to 2000 kg of straw per hectare (ICRISAT 1997). This corresponds to a yield of about 500 kg of millet grain per hectare. Mulching may increase yield by 50%. The straw lowers the temperature on the surface, reduces erosion, improves the phosphorous content and increases soil organic matter content (Buerkert et al 2000). However, it is difficult to have such straw quantities without microdosing since the straw is also used for other purposes. Thus, microdose makes mulching more feasible. The straw must be cut just after the harvest and the stems must be left in the field. This also helps reduce attacks by stem borers. However, it is difficult to practice mulching because of roaming animals in the dry season, leading to reduced quantities of the available straw.

Certain trees can be used for mulching. The most promising tree in the production of green manure is the Acacia tumida. According to a study by ICRISAT, Acacia tumida leaves do not decay rapidly and the nitrogen release is not significant in the course of the first years. The effect of the Acacia tumida mulch is rather to lower soil temperature, reduce erosion and to increase soil organic matter. Moreover, the Acacia tumida live fence will reduce the speed of the wind and consequently the loss of water from the fields (see chapter on the tree).  

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