Circle of petals (7)
I believe the answer is:
corolla
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">circle of petals</span>' is the definition.<br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for corolla that I've seen before include "bit of a bloomer" , "Flower's petals collectively" , "part of plant" , "Internal whorl of a flower" , "Whorl of flower petals" .)