Coco peat and peat moss are the main Hydroponic bedding substrates widely used in the country and totally supplied through imports. Coco peat obtained from coconut shells waste and peat moss from natural forest- or marsh-lands. Regarding the expansion of greenhouse cultivation, especially soilless culture systems, use of coco peat and peat moss are also growing that impose considerable costs for the country. Because of its suitability, pine tree is a dominant specie, especially in semi-arid and arid regions of our country, producing large amounts of leaves and pine cones annually, that are not of a quality for use as animal feed or industrial applications. Due to its resistant to drought and salinity stresses, Berry is also another specie, in recent years, considered as an alternative tree for urban green space which results in production of large volumes of annual pruning wastes that may turn to economic benefits, if properly managed. Therefore, this research was carried out to investigate the composting of the above mentioned wastes as hydroponic bedding substrates to replace coco peat for growing sweet pepper seedlings. Based on the results, the pine leaf wastes showed the most weight loss during the composting process. Some other physical and chemical properties such as bulk density, real density, EC, pH, cation exchange capacity, and the content of hemicellulose, cellulose and lignin of the residues were also measured before and after the composting process. The bulk density increased with composting. The real density remained relatively unchanged while the electrical conductivity was increased after composting. The initial pH was acidic, but composting raised the pH close to the neutral range. The cation exchange capacity increased in the composts as compared with the initial wastes. The hemicellulose and cellulose contents of wastes decreased during composting, while the lignin increased. The produced composts showed higher levels of nutrient elements over the coco peat except for potassium. The lignin content and also the water retention capacity of coco peat were higher than the composts as well. The CEC and concentration of cellulose in the composts and coco peat were almost similar. Application of the produced composts as bedding substrates for growing pepper seedlings in comparison with coco peat was also tested in a completely randomized design with 7 treatments and 3 replicates. Treatments included pine cones compost (50%) + perlite (50%), pine leaf compost (50%) + perlite (50%), berry prunings compost (50%) + perlite (50%), pine cones enriched compost (50%) + perlite (50%), pine leaf enriched compost (50%) + perlite (50%), berry prunings enriched compost (50%) + perlite (50%) and coco peat (50 percent) + perlite (50 percent). Three kg capacity pots were filled with the bedding substrates and two seedlings of pepper were planted in each pot. The pots were kept in natural light in a greenhouse and nutrient solution provided by a drip system. After 2 months the plants were harvested and some growth parameters were measured. Statistical analysis and comparison of means using the least significant difference (LSD) at 5% probability performed using SAS. The results showed that the plant performance grown in the produced composts was similar to those in coco peat, while the enriched composts of pine leaves and berry prunings were relatively superior than coco peat , although the differences were not statistically significant. Key Words: bedding substrates, hydroponic, pine cones, pine leaves, berry prunings, sweet pepper, coco peat.