Flower best put below daughter's computer (7)
I believe the answer is:
desktop
'computer' is the definition.
(desktop computer is a kind of computer)
'flower best put below daughter's' is the wordplay.
I cannot really see how this works, but
'best' could be 'top' (top can mean the very best) and 'top' is found in the answer.
'daughter' could be 'd' (genealogical abbreviation) and 'd' is present in the answer.
The remaining letters 'esk' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for desktop that I've seen before include "Office work surface" , "Location of icons" , "often supports a mass of papers?" , "Working surface, computer screen area" , "Publishers'" .)