Summer tree watering guidelines

Summer tree watering guidelines

Published on August 17, 2026

During hot summer months, trees play an important role in shading our neighborhoods and reducing cooling costs. However, when the soil dries out, even healthy trees can struggle. Below are tips to follow when caring for trees during hot weather.

Caring for young trees (planted within 3-5 years):
Young trees have smaller root systems that are too shallow and small to access deep moisture.

• Soil moisture check: Check the top 2 inches of soil with a finger first-if damp, wait a day or two to water to avoid root rot.
• Watering: Do so every 3-5 days. Water the area directly around the root ball and extend the watering slightly beyond it.

• Mulch matters: Apply a 2-4 inch layer of wood chip mulch over the root zone to retain moisture, keeping it a few inches away from the trunk.

Caring for mature trees:
Established trees need deep, infrequent watering that reaches 12-18 inches deep.

• Target the drip line: Water the critical root zone under the outer canopy edge, not the trunk. Keeping the trunk dry prevents fungal disease and rot.
• Water deeply and slowly: Use a soaker hose or slow trickle for 1-3 hours to prevent runoff. Test depth by pushing a screwdriver into the soil; it will slide easily through wet dirt.
• Timing and frequency: Water early morning or late evening to minimize evaporation. A thorough soak once or twice during peak summer is often all mature trees need.

By taking a little time to deep-water your trees this summer, you are protecting our urban forest and helping Menlo Park's canopy remain healthy and vibrant.

For information on City tree programs, visit menlopark.gov/trees. To request inspection or maintenance for City trees, visit menlopark.gov/ACT.

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