We've had a few weeks of high heat in the 80's to 90's with no rain. I water every 3 to 4 days but occasionally more often if serious heat or plants start to wilt. Peppers curled their leaves in the course of one day last week. Not very dry or yellow looking, just slightly curled. Frequent watering seems to have helped a little but still curled. Is it just lack of water or is it more than that? Thanks!