Chrysanthemum plants sold to produce what you may call florist flowers,
spray and bloom as well as "Garden mums" are all raised from cuttings taken
from the previous years stools (the old plant after the flowers have all
been cut).
Most growers (Unless they want to take their own cuttings) treat them as
annuals.

--
David Hill
Abacus nurseries
www.abacus-nurseries.co.uk