Flowers Lisa had arranged (7)
I believe the answer is:
dahlias
'flowers' is the definition.
(dahlia is a kind of flower)
'lisa had arranged' is the wordplay.
'arranged' is an anagram indicator (letters rearranged).
'lisa'+'had'='lisahad'
'lisahad' is an anagram of 'DAHLIAS'.
(Other definitions for dahlias that I've seen before include "Tuberous Mexican flowers" , "I had Al's fowers" , "Might Ali dash for the flowers?" , "Herbaceous perennial plants of a Mexican genus" , "Tuberous garden plants" .)