Bush envoy opening Republican art venue (5)
I believe the answer is:
erica
'bush' is the definition.
(erica is a kind of bush)
'envoy opening republican art venue' is the wordplay.
'opening' says to take the initial letters.
'republican art venue' becomes 'rica' (I am not sure about this - if you are sure you should believe this answer much more).
The first letter of 'envoy' is 'e'.
'e'+'rica'='ERICA'
Can you help me to learn more?
(Other definitions for erica that I've seen before include "I care about Heather, oddly" , "Heather's Latin name?" , "Girl - heather" , "growing up on the moors" , "Shrubs" .)