The most common and most likely answer to this crossword clue is the 7 letter word RAISING
I've seen this crossword clue in The Daily Telegraph
R
A
I
S
I
N
G
Buddy explains!

The straight part
We know that "Growing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case growing = raising.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 RAISING mean?
RAISING verb- (physical) To cause to rise; to lift or elevate.
- To create, increase or develop.
- To establish contact with (e.g., by telephone or radio).
- To respond to a bet by increasing the amount required to continue in the hand.
- To exponentiate, to involute.
- (of a verb) To extract (a subject or other verb argument) out of an inner clause.
- (of a vowel) To produce a vowel with the tongue positioned closer to the roof of the mouth.
- To increase the nominal value of (a cheque, money order, etc.) by fraudulently changing the writing or printing in which the sum payable is specified.
- To throw (an exception).
- Elevation.
- Nurturing; cultivation; providing sustenance and protection for a living thing from conception to maturity
- Recruitment.
- Collection or gathering, especially of money.
- The operation or work of setting up the frame of a building.
- The movement of an argument from an embedded or subordinate clause to a matrix or main clause.
- A sound change in which a vowel or consonant becomes higher or raised, meaning that the tongue becomes more elevated or positioned closer to the roof of the mouth than before.
- The operation of embossing sheet metal, or of forming it into cup-shaped or hollow articles, by hammering, stamping, or spinning.
- The substance used to make bread rise.
- The process of deepening colours in dyeing.