Comparison of Vermicompost and Composts as Potting Media for Growth of Tomatoes

Vermicomposting and composting are efficient methods for converting solid wastes to useful products. Incorporation of composts and vermicomposts into potting and container media is a potential use for these materials. In a greenhouse trial, effects of a vermicompost produced from raw dairy manure (RDM) along with some other composts produced from tobacco residue (TR), yard leaf (YL), sewage sludge + rice hull (SS + RH), sewage sludge + yard leaf (SS + YL), and RDM were studied. The mixing proportions of vermicomposts and composts were 0, 15, 30, and 45% of pot volume and tomato seedlings were grown in pots. All potting mixtures produced significantly higher biomass than the control (soil + sand) and RDM. Shoot and root dry matters (DM) were greatest in VC and SS + RH. Rates of composts in potting mixture did not generally affect DM, although a decrease in DM was observed in pots containing 45% of SS + YL. TR and YL produced lower DM in comparison with VC, SS + RH, and SS + YL. Correlation coefficients between the amounts of nutrients added to the pots by composts and nutrients taken up by plants were in the following order: phosphorus (P) > zinc (Zn) > copper (Cu) > calcium (Ca) > manganese (Mn) > potassium (K) > nitrogen (N) > magnesium (Mg) > iron (Fe).