Suitability of cultivation of some perennial plant species on sewage sludge

In the years 1995-1998 an experiment with planting some perennial plant species on the sewage sludge purifying plant in Lublin was carried out. Since Ligustrum vulgare L. did not root, the studies were carried out on three species: Helianthus tuberosus L., Salix viminalis L. and Sida hermaphrodita R. During four years the number of Salix plants decreased, Helianthus plants showed the symptoms of damage and the Sida plants were a little weaker than in the field cultivation. The highest average stalk yields during the 4-year period were noted for Sida (6.85 t/ha of dry mass) and lowest for Salix (2.28 t/ha). Among the three species compared, Sida took up the highest amount of Cu, Ni, Zn, Pb, Co, Fe and Cr in stalks. The 4-year experimental results unambiguously point to Sida hermaphrodita as a useful species to grow on sewage sludge.