This year, my chives are inedible because they're covered in rust. The rust
has also spread to all the ornamental alliums nearby. Anti-fungus spray
hasn't done much to help the problem.

What, if anything, do I need to do to my ornamental alliums? Will they be
okay if I just leave them to do their thing then eventually die back
naturally? Or do I need to treat them in some way to prevent rust next
year?

Thanks.