Geraniums have been popular garden perennials for a long time, and have lots of devotees. Consequently, there are lots of good sources of information on the internet. A good start is provided by the Open Directory Project's geranium category. For a primer on erodiums, this page from the UK gives a good overview.
Stimulus control is the phenomenon of a stimulus increasing the probability of a behavior (operant response) because of a history of that behavior being differentially reinforced in the presence of the stimulus.
Definition of Locus of Control. A locus of control is a person's belief about how much power one has over the events in one's life. According to psychologist Julian Rotter, who formulated the concept in the 1950s, the locus of control is a dimension of personality; it helps explain one's traits and behavior.An internal locus of control is the belief that the course of one's life is largely up to oneself.Those with an external locus of control regard the events in their lives as occurring regardless of their own efforts. locus of control is a person's belief about how much power one has over the events in one's life.