Dude growing is the most zenful thing on the planet. I enjoy waking up to the sweet smell of my personal kushes, my separate rooms for indicas and sativas uhghghghgh. Its so lovely, anyways yellowing in the middle could just be nitrogen deficient, you shouldnt have any yellowing/discoloring in veg, they should always be nice a green. heres my veg room. only time i see yellowing is 2 weeks before harvest in flowering and thats cause im flushing during those 2 weeks. you want a yellow plant at harvest more green gone less chlorophyll thats in the leaves and thats what burns your throat.
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