Evaluation of morphological and chemical composition of seed geranium ‘Florever Deep Red’ F1grown in substrate containing municipal sewage sludge and potato pulp

Abstract

Development of various types of agronomic, industrial or municipal waste as components of horticultural substrates can be an alternative to other commonly used substrates in the production of ornamental plants. These studies were conducted to provide data on the possible usage of municipal sewage sludge (MSS) compost for the cultivation of 'Florever Deep Red' geranium (Pelargonium ×hortorum) propagated from seeds. Substrates were prepared from sphagnum peat (SP) and four composts containing MSS, potato pulp (PP), rye straw (RS) or sawdust of coniferous trees (SD). The composts RSQUO (C) composition was as follows: CI - MSS 70%, RS 30%; CII - MSS 70%, SD 30%; CIII - MSS 35%, PP 35%, RS 30%; CIV - MSS 35%, PP 35%, SD 30%. Composts were amended to peat at 25, 50 and 75% (by volume). Geranium seedlings were planted in pots and grown on tables in a plastic tunnel without top dressing. The results of the study indicate that it is possible to grow seed geranium in peat-based substrates amended with the different composts without the use of top fertilization. The quality and abundance of geranium flowering varied according to the substrate, which largely depended on the composition of the compost and compost rate in the mixture. The substrate containing MSS and RS compost at the highest rate had a positive impact on the abundance of flowering, inflorescence size and decorative value of the plants. The content of macro nutrients and heavy metals in the leaves of geranium depended on the composition of the substrate and increased with the rate of compost.