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The Carnivorous Plant FAQ: How often should I feed my plant?
I've always had bad experiences with venus fly traps. I do think they need to have good soil and a good habitat before you do anything. Carn. plants do seem to mildew easily. I would strongly suggest if you feed it, try to feed to animals you buy from a breeder and not from a patio porch
(i did that once)
Good luck with the pitcher. Got any pics?