How much water does a street tree need?

How much water does a street tree need? We’re so glad you asked! Young trees and established trees need different amounts of water. 💧

🌳 Young Trees

The standard recommendation for young trees is 15-20 gallons per week, which means filling a green "gator" water bag once a week until the tree is about 3 years old.

Sandy soil, hot weather, infrequent rainfall, and strong winds are all reasons that a young tree could benefit from more water. Even in the rainy months, a 3x3 ft tree basin will get approximately 5 gallons of water per 1 inch of rain, which often doesn't add up to 15 gallons per week.

🌿 If you have a young street tree near you, adding extra water to the watering bag or directly to the soil once a week is a great way to help the tree establish a deep and stable root system. Just be sure that enough water is applied at a time so that the soil is moist a few inches below the ground (deep watering = deep roots), and that the soil has time to dry before you water again (watery swamp = root rot diseases.

Our tree care team, which includes community volunteers, makes about 3,500 tree care visits for pruning and health checks each year and waters on average 1,100 young trees every week

🌳 Established Trees

After trees are in the ground for about 3 years, weekly watering is no longer needed, and the water bag may no longer be as effective.

Trees at this stage can benefit from a periodic deep soak (which you can do with a hose or a bucket a few times a year), so that water continues to reach far down into the root system, which at maturity is often between one to two feet below the ground.

Friends of the Urban Forest takes care of the trees we plant for the first 3 years of their life. After the first 3 years, San Francisco Public Works takes over.

If you see a tree, that needs care, please fill out a Tree Care Request Form.