I don't know if this has been posted before but here goes. Ziploc makes produce bags. I don't know why but I bought these and placed my collard greens in it. 3 weeks later they are just as fresh as the day I bought them. Of course you have to follow the directions for use but they really work. All other methods Ive tried my greens and fruits go bad in a little over a week. Just figured this might be able to help someone else.