Guess I should have elaborated more. What i meant with an emersed state of some form is anything from moist earth to being able to atleast pierce the water surface. Most can ofcourse survive just fine completely submerged. Like the the crypts I have in my own aquarium
If they are completly submerged all year round they can only reproduce vegetatively which is bad in the long run
I remember a huge collection of crypts this botanist professor had where i used to work. It was pretty darn big, and i don't recall a single of them growing 100% submerged.