Gathers together in a cold island country needing sun (8)
I believe the answer is:
accretes
'gathers together' is the definition.
'accretes' can be an answer for 'gathers' (accreting is a kind of gathering). I am not certain of the 'together' bit.
'a cold island country needing sun' is the wordplay.
'cold' becomes 'C' (eg on taps).
'island country' becomes 'crete' (I am not sure about this - if you are sure you should believe this answer much more).
'needing' is a charade indicator (letters next to each other).
'sun' becomes 'S' (abbreviation).
'a'+'c'+'crete'+'s'='ACCRETES'
'in' is the link.
Can you help me to learn more?
(Another definition for accretes that I've seen is " Grows by accumulation -- races etc (anag)".)