WITH OUT PICS THE BEST I CAN EXPLAIN. My plant about 2 months old is growing great but the newest growth at top of plant just showed about 10% of the leaf brownish blackish wierd color... Like blotches I had another plant next to this one a few weeks back that had that same thing on most leaves so i cloned it and killed it, is it some fungi that jumped to this plant? I dont think its nutrient related cus it was on a plant I didnt give much nutes ???
go to the sick plant forum. the first handful are stickies. read em. they got pics and explinations. good luck.