Dewitt Dew Right Tree Watering Bag 20GEliminate the severe water stress that new trees endure after transplanting. This tree watering bag is designed specifically to increase first year survival rate and set the stage for a long, healthy life. 20gal bag empties in five to eight hours and only needs to be refilled one or two times per week for most trees. Installs easily in just five minutes, without tools. A single bag fits trees up to 3in in diameter. Zip two bags together to fit a 3in