In Bulgaria there still exist undecided issues regarding the growing technology of Callistephus chinensis. The aim of this study was to investigate the influence of three biostimulators – Kendal, Megafol and Radifarm, on the qualites and seed production of asters. The multiplicity and doses of treatment were consistent with the prescriptions of the manufacturer. The tested varieties were Princess sylvis and Harzyrus, the indicators taken into consideration being the length of flowering I order, I inflorescence diameter range, productivity and quality of the seeds.
The results reflected the positive impact of the treatment on the development and decorative traits of the plants. The use of the biostimulators increased the seed production by 0.42-0.67 g/plant (Princess sylvis) and by 0.27-0.55 g/plant (Harzyrus) compared with the control. The seeds were characterized by higher economic qualities.