Determining the best seeding and duration of the cultivation period in N'djaména and surroundings-Chad

Curves of time variations of evapotranspiration and precipitations have been plotted, their points intercept determined. This enable us to find out the seeding period and the duration of the useful rainy season which corresponds to the cultivation period in N’djaména and surroundings for the years from 1980 to 2007. This study has shown that the confortable time to begin planting is mid-July, the average duration cultivation period, from the moment of planting to the harvest, is fifty days. Outside this laps of time irrigation should be unavoidable.