The most common and most likely answer to this crossword clue is the 8 letter word BRASSICA
I've seen this crossword clue in Independent
B
R
A
S
S
I
C
A
More clues leading to the result BRASSICA
- Slangily, ‘money’, to begin with, is called by American ‘cabbage’
- Artists tucked into basic mashed vegetable
- Vegetable in tin
- Maybe cabbage and bread the above regularly rejected
- Money one accountant needed for certain plants
- Exotic scarab is in plant
- Cash for individual’s California plant
- One about to chase money for vegetables
- Veggie family having fool and most of ice in two cups
- Slangily, 'money', to begin with, is called by American ‘cabbage’
Buddy explains!

The straight part
We know that "Vegetable" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vegetable = brassica.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 BRASSICA mean?
BRASSICA noun- Any of many plants of the genus Brassica, including cabbage, mustard and rapes