Contract farming frequently takes place in extensive rural areas where particularities of the crop determines the economic cycle and livelihoods of the population. Despite the existence of many settlements and small towns in these areas, one urban center often takes the primary position in terms of broader and more encompassing economic activities and service facilities than the other settlements. These rural centers follow specific economic rhythms that are linked to the seasonality and other characteristics of the crop, e.g. logistics, storability, processing requirements, etc. The impact of these growth dynamics are important not only on the immediate ‘catchment area’ of the center but also on regions beyond this, for instance in regions that traditionally function as supply pools of labour. This paper aims to trace the patterns and trajectories of urban growth to the different characteristics of sugarcane and tobacco. The two crops have distinctive properties and offers different possibilities for the establishment and expansion of new backward and forward linkages as well as economic and social upgrading of existing activities. Sugar cane requires large-scale processing and need highly organized logistical systems while tobacco is storable and collection after harvest is straightforward. Purchasing prices of both crops depend on relatively opaque quality criteria. We argue that these differences and similarities of crop characteristics have a pronounced importance for the different growth trajectories of two rural centers that have a dominant position in their catchment area, namely Ruaha in Morogoro (sugar cane) and Urambo in Tabora (tobacco).