Poor writing in ledger, go bananas! (8)
I believe the answer is:
doggerel
'poor writing' is the definition.
'doggerel' can be an answer for 'writing' (doggerel is a kind of writing). I am not certain of the 'poor' bit.
'ledger go bananas' is the wordplay.
'bananas' indicates anagramming the letters (informal term for mad).
'ledger'+'go'='ledgergo'
'ledgergo' is an anagram of 'DOGGEREL'.
'in' is the link.
Can you help me to learn more?
(Other definitions for doggerel that I've seen before include "Trite verse" , "Nonsense verse" , "Worthless verse - gored leg (anag)" , "Poor quality comic or trivial verse" , "Burlesque verse" .)