Replacement of a Peat-Lite Medium with Municipal Solid Waste Compost for Growing Melon (Cucumis melo L.) Transplant Seedlings

The production of high quality seedlings for transplant involves several cultural inputs, of which potting-substrate quality stands out as perhaps the most important. The suitability of compost derived from municipal solid waste (MSWC) as a horticultural potting-substrate was compared with the popular sphagnum peat. Five media prepared from black peat (BP), white peat (WP), perlite and MSWC were used to determine the optimum growing medium for melon (Cucumis melo L. 'Eros') transplants. The substrate mixtures used were (% v/v): BP (65%) + WP (30%) + perlite (5%), BP (65%) + MSWC (30%) + perlite (5%), WP (65%) + BP (30%) + perlite (5%), WP (65%) + MSWC (30%) + perlite (5%), and MSWC (65%) + WP (30%) + perlite (5%). Plants grew in these mixtures for 25 days, with no additional fertilization. Various seedling indices were measured in order to assess the quality of nursery-produced plants. Most seedling parameters were significantly influenced by the potting-substrate used. MSWC application rates of > 30% reduced plant growth due to high salt and pH levels. Growth experiments showed that substrates containing 65% black peat and 30% MSWC appeared to be the most suitable growing medium for melon seedlings; proper leaching is recommended prior to use.