I don't know how I managed to add that up wrong but it was awhile ago so never mind; glad the Count is here to correct me on my maths...
I've went back and checked the episode and the choir is as follows, with tem members:
Grapefruit, Cabbage, Grapes, Scallion/Spring Onion
Cauliflower, Asparagus, Three Potatoes Joined Together, Tomato, Artichoke, Watermelon
"We have string beans" was the water melon
"And hav onions" was the cauliflower"
"And scallions" was the spring onions/scallions
No eggplant appears in this song
When I originally posted this list, I ws unsure whether the watermelon (bottom right if any of you have the clip) as either a melon or a marrow of somesort, but I rememeber someone telling me that yes, it was a watermelon.