Why are canna leaves brown before even opening up
The leaves of the plant are very brown before they open up and full of holes as well.
Probably your plants have canna leafrollers, just about the only insect that troubles canna lilies. This article tells you more, and what to do about them. https://aggie-horticulture.tamu.edu/galveston/weekly_q&a/f&b_11.htm