What is the Singular possessive of -fern-.... and WHY?
The singular possessive of most words is
's
fern's fronds
friend's house
boy's room
Yes, the plural of fern is ferns.
Most plural nouns add the apostrophe after the s.
Singular: fern
Plural: ferns
Singular possessive: fern's
Plural possessive: ferns'
I have one fern in a pot. The fern's pot is too small.
I have several ferns growing in my yard. The ferns' fronds have started to wilt.