The results showed differences in total dry weight related to changes in physical media properties when soil and river waste were added to a basic medium with peat moss, perlite and vermiculite (Substrato Van Leeuwen,}. Growth of Begonia semperflorens plants decreased when more than 80% of both amendments for container media were used. River waste amendment showed the best results. There was an increase in dry weigth for Gerbera jamesonii plants when river waste between 40-100% was used. Impatiens walleriana showed the best result at heavy container media (between 40 and 60% of organic soil amendment). By the other hand, there were no significant differences for Viola wittrockiana plants in container media with different physical properties. The changes observed in physical properties during growth cycle (total porosity, air porosity and bulk density) would be relafed to different patterns in root system growth for the four annual pot plants tested in this work.
