Best time for mowing meadow, do we hear? (6)
I believe the answer is:
heyday
'best time' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for heyday that I've seen before include "The period of greatest prosperity or productivity" , "Successful period" , "One's peak period" , "Period of greatest success and popularity" , "Highest period in someone's career" .)