Possible Clues:

• ... what's proverbial for the course, bargain vegetable
• Vegetable cut, no point having to cut again
• Ran pips out of the vegetable
• They have a point to knock up to get the root of this
• A white root vegetable
• Bargain on the regular amount for vegetable
• Upset, puts the blame on food
• Pale carrot-like vegetable
• Musical monologue about prune root
• Vegetable grown underground