Interesting to learn about seedling with more than 2 cotyledons, I've never had this happen with any of my tomatoes yet.
Fron the sounds of it, they are bad for saving seeds, but may have extra vigour? More foliage=more fruits or more sugar for the fruits from extra photosytnesis?
I would deffo baby any 3-cotyledon seedling I found more than usual!
Would be intersting to see how this one devolops and what happens with germination if you collect any seeds
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