A study was carried out in the University of Agriculture, Abeokuta, to identify a niche for growing green manure
in the derived savannah of Nigeria. Two local cowpea varieties were grown on 20th and 27th of March and 3rd
of April 2009; 10th, 17th and 24th March, 2010 in a 2 × 3 factorial arrangement in a randomized complete block
design. Open pollinated maize was planted as a test crop a week after incorporation of the green manure. Total
biomass of cowpea was low in 2009 relative to 2010. Cowpea green manuring led to grain yield increase of
succeeding maize by 92 -131 % and 43-124 % in 2009 and 2010 respectively. The erratic rains in mid March to
first week in April could provide sufficient moisture for the growth of cowpea for green manure in this
ecological zone and could ameliorate the effect of drought condition occasioned by climate change.