Highly desirable (4)
(Other definitions for enviable that I've seen before include "Privileged - to be desired" , "Causing a desire to have what another has" , "Likely to cause jealousy" , "sought-after" , "Desirable enough to make one green-eyed" .)
'highly desirable' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for to die for that I've seen before include "Highly desirable or alluring" , "hot" , "Extremely desirable (colloq.)" , "Superb" .)
'highly desirable' is the definition.
(plum can mean excellent)
This is all the clue.
(Other definitions for plum that I've seen before include "Damson-like fruit" , "Prize" , "Much valued -- fruit" , "Dark bluish-red - fruit" , "Edible oval fruit" .)