Watering Trees in Sandy Soil: Don't Overwater

Finding the Right Watering Schedule for Mulched Trees

A Southern California high-desert gardener waters 10 tree species every Monday, but by Thursday the soil under 4 inches of mulch is still moist. They ask if they should continue watering on schedule or let the soil dry.

Expert Advice

• Let the top 2 inches dry out before watering again. This encourages deeper root growth and drought resilience.
• Check under the mulch; if the top couple of inches are dry, water deeply.
• Apply 1 inch of water per session (measure with a pan under the sprinkler).
• Mulch holds moisture—adjust frequency, not volume.

Japanese maples and Douglas firs are sensitive to both drought and waterlogging. Deep, infrequent watering is best.