The purpose of this study is to address drought risk to cowpea farmers by identifying possible mixed lots of seed that spread risk. The method employed was a Poisson regression model using multi-year data for flowering time for 160 cowpea accessions. Two possible pairs of varieties for mixed seed release were identified, 1393-1-2-3(-) paired with Cameroon 12-58 and Sasaque paired with Tvu-9557. This study provides a new tool that can be used to predict the crop cycle for the lines and environments in the data set, which were in Pobe and Kamboinse, Burkina Faso. Further studies should consider consumer preferences, yield, disease resistance, and seed type.