See main article: ABC Theory formation of flower
The formation of flowers have long been a concern of people, because a lot of the economic value of crops cultivation depends on the formation of flowers. Interest will not be
formed before the network where it would appear has reached a stage of maturity (maturity) but not too old (senile).
In plants, tree-shaped network of the newly-formed or still developing (juvenile) will be very difficult to form a flower. The network reached a stage of maturity is often marked with a carbon-nitrogen ratio (the ratio of C-N) is high. The high carbon content because it has been widely covered in the form of metabolites of polysaccharides in the network. The formation of flowers requires great energy.