The canna cultivar ‘Tropicanna’ does not produce seed and is
considered to be sterile. It does produce pollen of very low viability. Should
you succeed in successfully pollinating your green leaf canna with the pollen
from Tropicanna and assuming your green leaf canna is capable of producing seed
you would still NOT get variegated offspring. You would likely be wasting a lot
of time trying.

When dealing with “cannas”, variegation typically is the
very rare result of a very specific mutation occurring at a specific location
typically on the meristem growing tip. This is much more likely to occur on the
rhizome and would not be related to pollination. The point here is that mutation
and not pollination is the prime mover for variegation in cannas.

For the record: our hybrid cannas do not breed true from
seed; our true specie cannas are considered to breed true and the seed strain
cannas available on the market today produce offspring that share physiological
identities. Sorry for the dissertation.

Kent