effect of different ratios of municipal solid waste compost on growth parameters and yield of marigold (calendula officinalis moench.) and daisy (bellis perennis l.).

in a country like iran, where soil organic matter is less than 1% and in most cases even less than 0.5 %, municipal solid waste (msw) is a permanent and inexpensive source of organic matter. various experiments have indicated that applications of compost improve plant health, yield and nutritional quality. however, the quality of the compost determines the growth and the development of plants. the purpose of this study was evaluating the effect of different ratio of organic compost from urban waste on the growth of two ornamental plants, marigold (calendula officinalis monch.) and daisy (bellis perennis l.). five treatments (potting-mixes) were used, soil (clay, silt and sand with 1:1:1 ratios) (as a control),the soil with  25% compost, the soil with  50% compost, the soil with  75% compost and 100% compost. fresh and dry-weight of shoots and roots, plant height, and chlorophyll content were measured. the results of this study confirm the beneficial treatment to improve the growth parameters is 25% and 50% compost in alendula officinalis and 25%compost in bellis perennis.