Tree starts to blossom, and our bushes are blooming! (6)
I believe the answer is:
baobab
'tree' is the definition.
(baobab is a kind of tree)
'starts to blossom and our bushes are blooming' is the wordplay.
'starts to' indicates taking the first letters.
The initial letters of 'blossom and our bushes are blooming' is 'BAOBAB'.
(Other definitions for baobab that I've seen before include "The monkey bread tree" , "Monkey-bread tree" , "Gigantic tropical tree with very thick trunk" , "Thick-trunked tree" , "Tree indigenous to Africa and Australia" .)