Instrument anxious gardener carries round (4,5)
I believe the answer is:
reed organ
'instrument' is the definition.
(I know that reed organ is a type of organ)
'anxious gardener carries round' is the wordplay.
'anxious' indicates anagramming the letters (an anxious or disturbed version of the letters).
'carries' is an insertion indicator (inserted letters carried inside).
'round' becomes 'o' (round can mean a round object).
'gardener' with letters rearranged gives 'reedrgan'.
'reedrgan' enclosing 'o' is 'REED-ORGAN'.
(Other definitions for reed organ that I've seen before include "Melody Maker?" , "supports traditional services" , "Keyboard instrument, harmonium" , "What you might hear" , "small instrument" .)