The most common and most likely answer to this crossword clue is the 4 letter word FLOR
F
L
O
R
More clues leading to the result FLOR
Buddy explains!
The straight part
We know that "Growth in wine-making" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case growth in wine-making = flor.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 FLOR mean?
FLOR noun- A film of yeast that develops on the surface of some wines during fermentation, induced deliberately during the production of sherry.