Research goal: The aim of this research was therefore to evaluate whether there are interactions in the growing medium in the simultaneous use of algae and beneficial microorganisms, to assess the possible improvement of flower quality and growth of succulent plants and the possible bioncontrol against pathogens present in the farm soils. Materials and Methods: The experiments, started in March 2021, were conducted in the greenhouses of CREA-OF in Pescia (PT), Tuscany, Italy (43°54′N 10°41′E) on Aichryson punctatum, Lewisia cotyledon, Crassula sarcocaulis, Kalanchoe orgyalis. The experimental groups were: i) group control, irrigated with water and substrate previously fertilized; ii) group with algae irrigated with water and substrate previously fertilized; iii) group with beneficial bacteria irrigated with water and substrate previously fertilized; iv) group with algae and beneficial bacteria irrigated with water and substrate previously fertilized. Results and Discussion: The trial showed a significant improvement of agronomic parameters analyzed on plants of Aichryson punctatum, Lewisia cotyledon, Crassula sarcocaulis, Kalanchoe orgyalis treated with algae, bacteria and using a mixture of algae with bacteria. In particular, the trial showed that the use of algae and bacteria can increase plant height, number of leaves, vegetative, root and flower weight, and flower duration. In addition, the treatment with algae and microorganisms showed how the use of algae and bacteria can increase the protection from the attack on plants, of pathogens such as Rhizoctonia solani and Fusarium oxysporum. It is shown that the combined treatment algae plus microorganisms was significantly better than using the two treatments individually. Conclusions: Scientific evidence confirms that the use of algae and microorganisms can play a particularly important role in improving the physical, chemical and microbiological quality of the soil and in biofertilization, biostimulation and plant protection. KEY-WORDS: Cyanobacteria; Sustainable agriculture; Beneficial bacteria; Succulent plants; Algae-microorganisms interaction