Improving growth characteristics of Ficus benjamina cv. Starlight using mushroom compost in the potting substrate

Application of suitable substrates is important for growing ornamental plants. Mushroom compost is considered as a waste in mushroom production. An experiment was done in a completely randomized design including the following treatments: substrates containing 50% cocopeat + 50% mushroom compost, 50% composted forest trees+ 50% mushroom compost, 50% perlite+ 50% mushroom compost, 50% leaf compost+ 50% mushroom compost and control substrate (70% agricultural soil+ 20% leaf compost+10% rice husk). The comparisons were carried out in 4 months; April, May, June and July and the the effect of different substrates were evaluated on the growing characteristics of Ficus benjamina</em> cv. Starlight.  The result showed the effect of substrate was significant on factors such as new leaf number, length and width of leaves while it wasn't significant on factors such as height, stem diameter and chlorophyll content. Also the effect of treatment time was significant on new leaf number, height, length and width of leaves, and stem diameter. The interactive effect of potting substrates and treatment time were significant on stem diameter, new leaf number, length and width of total leaves too. However, they weren't significant on plant height. Evaluation of results showed the best substrates for mixing with mushroom compost, were cocopeat, perlite and composted forest trees. Also growing indices were higher in plants that were treated in June and July compared tothe plant treated in other months. In conclusion, potting substrates such as perlite, cocopeat and composted forest trees in combination with mushroom compost are suggested to be used in the greenhouses.