Stocks possibly of less worth in Flanders' banks (7)
I believe the answer is:
flowers
'stocks possibly' is the definition.
(stock is a kind of flower)
'less worth in flanders' banks' is the wordplay.
'less worth' becomes 'lower' (I can't justify this - if you can you should believe this answer much more).
'in' is an insertion indicator.
'banks' says to hollow out the word (remove centre letters) (the sides or banks of the word).
'flanders' with its centre taken out is 'fs'.
'lower' going inside 'fs' is 'FLOWERS'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for flowers that I've seen before include "Blossoms" , "Blooms" .)