The most common and most likely answer to this crossword clue is the 9 letter word OLEASTERS
I've seen this crossword clue in The Times
O
L
E
A
S
T
E
R
S
Buddy explains!
The straight part
We know that "shrubs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case shrubs = oleasters.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does OLEASTERS mean?
OLEASTERS noun- A plant in the family Elaeagnaceae,
- Cultivated olive trees that have re-naturalized, sometimes treated as a species Olea oleaster, the wild olive.