What are it's growing conditions? Could it be a fungus?

How about cold... mine are "cupping" ... and it's gotten cooler than they like.

How cool is too cool? The coldest it's gotten here since I planted mine is one night at 50. Of course, mine seemed to grow even better after that cold "snap." Temperatures are generally running 80 - 85 for a daily high and 60 - 65 for a nightly low of late. I'm getting a little cupping on some new growth.

Mine are outdoors in 4 gallon pots. They're growing in potting mix, which I water twice weekly. They have a direct southern exposure, and get full sun from sunrise to sunset. I fertilized once, about a month ago, with Peter's All Purpose. I've used no other chemicals.

My plants get patchy sun from about noon on. I water them about once a week, just before they start to look wilted. It doesn't get cold here. I live in southern California a couple miles from the ocean. I can't imagine it's a fungus - the plant looks fine except for the oddly shapped leaves.