Hibiscus - plural??

I was browsing the topics at 'another forum' today, and noticed they have one titled 'Hibiscuses'.....isn't the plural of Hibiscus, simply 'Hibiscus'??
(I note that DG's forum is simply titled Hibiscus)

I did a little searching online, and found that most sources say yes, but MSN's Encarta says 'Hibiscuses'.....hmmm....anyone know *for sure*??

(A little off topic yet on topic?!) lol!

Nobody knows????

I believe that the plural of hibiscus is hibiscus, but I could not find proof to back up my belief. Webster lists variant plurals for deer and goose, for example, but does not comment on hibiscus. I have hibiscus in my garden . . . I have hibiscuses in my garden . . . I have hibisci in my garden (on a Latin model) . . .
I like "hibiscus" as a plural best.

lol! Yeah, me too!