Cryptic crossword clue
Plots mum and dad start to rake with interest in retirement 3,6

The most common and most likely answer to this crossword clue is the 3 plus 6 letter word BAR GRAPHS

I've seen this crossword clue in The Guardian
B
A
R
G
R
A
P
H
S

Buddy explains!

The straight part
We know that "Plots" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case plots = bar graphs.
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.

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