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The most common cause of marijuana leaf cupping aka leaf margin rolling, leaf margin burn, and leaf tip curl/burn is overzealous use of marijuana plant food. In relationship to factors such as marijuana plant vigour and rate of growth. Leaf burn is often the very first sign of too much marijuana fertilizer.
If your dryness problem is just affecting the oldest leaves that don't get much light anymore, you shouldn't worry. If the leaves affected are the ones which are closest to your lights, it's possible that the crispiness is a result of 'light burn' or 'heat burn'. You can tell if this is the cause because the only cannabis leaves affected are the ones closest to the lights or source of heat. If the dryness affecting leaves that are new growth, it's possible that you are you are giving your cannabis too many nutrients and it's showing the first signs of nutrient burn.