Could be a nutrient issue. Most often it is over fertilizing. Heat, over watering and under watering can cause issues as well.

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KanMan Reviewed by KanMan on . Newbie Needs Help....Leaf edges curling upward... Whats up fellow plant lovers....I have been following this forum for couple of months and decided to give it a shot, but need some help. Started with stash seeds for first time, flo's and miracle gro. I have eight to start and have kept a close eye on PH, still in veg. state 35 days and plants look great, But, the edges of the leaves on the tops of certain plants have started to curl upward down the length of the leaf. Is this the start of something bad or what? I've followed all of Rating: 5