for example, you may create a theoretical
Rudbeckia fulgida subsp. fulgida var. sullvantii f. alba cultivar Josephine
then the name will be Rudbeckia fulgida 'Josephine'
the cultivar is not a variety or form,
subspecies - subsp.,varieta - var.,form - f. they are naturally created
the cultivar is artificially cultivate - by selecting the random variation, or targeted crossing, mostly differ just paint flowers
