Compost substrates based on sewage deposits, tannery sludge as well as coconut fiber can become an alternative for peat substrates in the cultivation of ornamental plants. The use of municipal deposit composts to fertilise soils increases their organic mass content, which, as a result of the humidification processes, improves their physical properties, sorptive capacity, creates a lumpy structure and enhances the microbiological activity in soils. The aim of the research was to assess the use of nutrients contained in substrates produced with the use of municipal sewage deposits and coconut fibre in the cultivation of the horned violet. In 2005-2007, experiments were conducted using six horned violet cultivars (Viola cornuta) from the Patiola F1 group. Four organic substrates were used in the research: I - sphagnum peat, II – coconut fibre, III – peat and compost substrate 1 (1:1 v/v), IV – peat and compost substrate 2 (1:1 v/v). Compost 1 was prepared from municipal sewage sludge (35%), potato pulp (35%) and straw (30%). Compost 2 was made from municipal sewage sludge (35%), potato pulp (35%) and sawdust (30%). Both of them were composted for 10 months. The following chemical analyses of the composts, their components and substrates after plant cultivation were performed: pH; dry matter content, total nitrogen, total phosphorus, total potassium, calcium and total magnesium, cadmium, copper, manganese, nickel, lead, total zinc. The compost substrates made from municipal sewage deposits were rich in nutrients and provided the plants with their appropriate amounts. The composts from municipal sewage waste also contained considerable amounts of heavy metals; however, their levels did not exceed the concentrations allowable in mineral soils intended for cultivations and lands.

19.4.2014