Good players make bloomers (5)
I believe the answer is:
seeds
'good players' is the definition.
'seeds' can be an answer for 'players' (seed is a kind of player). I am not sure about the 'good' bit.
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for seeds that I've seen before include "Favoured entrants in a knock-out competition" , "Initiates the growth of" , "Genesis" , "Small hard fruits" , "top tennis players" .)