Landscape neutral models are not frequent in the agronomic domain, whereas they would be very useful for studying several agro-ecological or physical processes. As opposite to ecological neutral models, agricultural models have to represent and manage geometrical patches together with their soil occupancies and thus should rely on tessellation methods. In this paper we present \genexp, a software for simulating neutral agricultural landscapes based on tessellation methods, that was primarily designed for simulating gene flow at a landscape scale.