A completely randomized two-factorial experi-ment was carried out under natural conditions over a four-week period with topsoil (0–0.30 m depth) from an alluvial soil and subsoil (0.40–0.60 m depth) from a brown soil derived from loess. The topsoil is characterized by a higher amount of available nutrients and by higher concentrations of total organic carbon and of nitrogen (Table 1).The soils were filled into Ahr pots (12 kg topsoil and 13 kg subsoil per pot) and were fertilized with 20 g/pot (subsoil) and 15 g/pot (topsoil) of a com pound fertilizer (12% N, 5% P, 14% K as sulphate, 6% S, 2% Mg). After emergence, seedlings were thinned to 25 plants/pot. 13 days after sowing, the soils were irrigated to 70% of maximum water-hold-ing capacity in one treatment and to 110% of the maximum water-holding capacity in the treatment of water logging. For each soil and plant species, all treatments were replicated four times. Plants were harvested when the first symptoms of yel-lowing of older leaves occurred. These symptoms were visible 15 days after water logging treatment. In this experiment, it was not possible to separate the roots from the soil by washing because in the water logging treatment a part of the root system was degraded and roots were destroyed by the washing procedure.