The most common and most likely answer to this crossword clue is the 8 letter word GARDENED
I've seen this crossword clue in The Sunday Telegraph
G
A
R
D
E
N
E
D
Buddy explains!
The straight part
We know that "Worked on plot," is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case worked on plot, = gardened.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 GARDENED mean?
GARDENED verb- To grow plants in a garden; to create or maintain a garden.
- Of a batsman, to inspect and tap the pitch lightly with the bat so as to smooth out small rough patches and irregularities.
- Having gardens or maintained like a garden.