In article , doug
writes

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Many years ago when I was a boy it was quite common to find tomato plants on
the wasteland heaps out the back, some with potatos on the roots.

Are you sure you were not simply finding potato plants in fruit and
mistaking them for unripe tomatoes?

I think the two species are of the same genus.

No, they are not. Potatoes are Solanum, tomatoes are Lycopersicum. They
are, however, in the same family (along with deadly nightshade,
aubergine and sweet peppers).

--
Kay
"Do not insult the crocodile until you have crossed the river"