I first noticed this about 5-6 weeks into vegetative growth. There are a lot of leaves that are curled down, but not colored like this. I'm thinking this is a mutation, but the sharp downward curl may be from something else. I welcome any comments. The plant is in flower now and about 2 weeks from harvest. The yield looks like it will be great! BTW...it's Durban Poison and I'm growing in 3 gal cloth pots.