Cove Four TRCR4 TreeCOVEr 15-Gallon Slow Release Tree Watering Bag Heavy duty watering bag for trees 15 Gallons of water provide drip irrigation for 5-9 hours, allowing water to penetrate deep into the root system Reduces planting shock with newly planted shade trees Two bags can be zipped together for a 30 gallon watering system Can be re-used season after season