Possible Clues:

• Welsh vegetable symbol
• Scallionlike vegetable
• Vegetable that's a Welsh symbol
• Potato's partner, in a classic soup
• Bulb
• By the sound of it, escape from Wales
• Vegetable in need of a plug, we hear
• Spill the beans, say, and find another vegetable
• Growth in list is reversed
• Hot or cold soup ingredient