We use both a panel of district data for a nearly 20 year period (1991-2008) and a panel of
household survey data (2010 and 2013) of Malawi to investigate the contribution of water to
productivity in rain-fed agriculture. Production function estimations suggest a larger contribution
to production from rainfall than from chemical fertilizer. We supply evidence that (uncertainty
of) supply of water is a key determinant of the crop choice of farmers, and more specifically, the
choice between, on the one hand, low input staple foods / subsistence crops, and, on the other
hand, high input and high value cash crops. We plan to claim additionally that chemical fertilizer
use depends critically on crop choice, notably the choice for high value cash crops, and thereby
on the availability of water. Finally, we provide evidence at household level that further supports
these claims. Our work gives an alternative explanation of observed low uptake of chemical
fertilizer by farmers and of the mechanism that drives fertilizer use in rain-fed SSA agriculture.