Shrub in untidy garden surrounded by fresh hay (9)
I believe the answer is:
hydrangea
'shrub' is the definition.
(hydrangea is a kind of shrub)
'untidy garden surrounded by fresh hay' is the wordplay.
'untidy' is an anagram indicator.
'surrounded by' means one lot of letters goes inside another.
'fresh' indicates an anagram.
'garden' with letters rearranged gives 'drange'.
'hay' with letters rearranged gives 'hya'.
'drange' put into 'hya' is 'HYDRANGEA'.
'in' is the link.
(Other definitions for hydrangea that I've seen before include "Showy flower" , "Flower you would find in garden hay" , "Shrub of the saxifrage family -- angry head (anag)" , "Flowering plant - angry head (anag)" , "Shrub - garden hay (anag)" .)