muffen

The leaves are actually coming out very cleanly, than I'll go out one day and instead of seeing inches of growth, they are collapsed and some of them "shreaded." I had been thinking about the water, but I'm really only watering them once a week right now since it is still cool. This is happening to all of my bananas, and as far as I know they are all the same species. My neighbors aren't big gardeners, so I doubt its pesticides, but I guess it is possible. Any thoughts on how to fix the situation so that my plants can actually get some leaves? Thanks