To be on the safe side try flushing the soil throroughly and see if the leaves perk up. If not, then get fertilizer, preferably organic. You either have a deficiency or toxic build up of something is preventing the uptake of something else.
MegaOctane12 Reviewed by MegaOctane12 on . New Leaves turning - Help ASAP - (Pictures included) I just want to get some advice on this plant before it gets any worse. I started to LST it this week and it's really beginning to fill in. But a few leaves are looking like this, let me know what to do (see pictures): Rating: 5