Plant not wanted by small daughter (4)
I believe the answer is:
weed
'plant not' is the definition.
'weed' can be an answer for 'plant' (I have seen 'Unwanted plant' mean 'weed' so perhaps 'plant' could also mean 'weed'). I am not certain of the 'not' bit.
'wanted by small daughter' is the wordplay.
'wanted by' says to put letters next to each other.
'small' becomes 'wee' (Scottish term for small).
'daughter' becomes 'd' (genealogical abbreviation).
'wee' next to 'd' is 'WEED'.
Can you help me to learn more?
(Other definitions for weed that I've seen before include "dope" , "Plant growing in the wrong place!" , "gardening" , "Ineffectual person" , "Uncultivated plant" .)