The addition of compost
to the medium positively influenced general plant
development at further stages of their culture. In the rhizosphere
of geranium, the number of actinomycetes recognized
as important phytohormone producers [1], simultaneously
doubled in comparison to the control. These
observations suggest that a positive effect of compost on
the rooting of Pelargonium peltatum hort. is related to
a significant degree with the activity of plant-promoting
rhizobacteria, the development of which is stimulated by
the addition of that biofertilizer to the greenhouse medium.