Sucrose storage during sugar beet growth is influenced by exogenous factors such as weather conditions and nutrient supply and their interactions with genotype. Water content, sucrose and non-sugar dry matter of the beet root depend on its cell size and structure. Apart from that, sucrose accumulation in the storage tissue is also limited by the content of other compounds that balance the osmotic potential within the cells. In order to study the relationship between sucrose storage and other constituents of the beet root under a wide range of environmental conditions, a trial series was carried out in 2000 and 2001 at eleven locations in different beet growing areas in Germany. Brei samples were taken from six or twelve subsequent harvests between end of May and end of October and the concentration of sucrose, beet marc (insoluble cell wall material) and betaine was analysed. The seasonal development of marc and betaine concentration was different at the trial sites. High sucrose concentration was accompanied by high marc as well as high betaine concentration at different locations. It is assumed that high sucrose concentration in sugar beet can only be achieved by forming cell structures to obtain the optimal cell volume for sugar storage and by simultaneously maintaining the osmotic balance in the cell by betaine accumulation.