Growing Beans In A Plastic Bag #Ideas Edit Place the beans in the sandwich bag with the wet paper towel and seal the bag. The beans will sprout in 3-4 days. Share this post Related PostsOnions Planting, Growing And HarvestingGreat Tips On Growing Peppers To Maturity #GardeningPlastic Potato Barrel #GardeningWhat You Need To Grow Shiitake Mushrooms #Gardening