Hydrangea Tree Stress: Drought, Disease, or Seasonal Fade?

A hydrangea tree (standard) in St. Louis that lost leaves and developed brown spots after a week without water in high heat is likely suffering from moisture stress. Hydrangeas need a deep soaking weekly; well‑drained soil can dry too fast. The flowers turning green‑brown is also normal seasonal aging.

Recovery Steps

• Water deeply once a week (more in extreme heat).
• Apply 2–3 inches of mulch to conserve moisture.
• Don't fertilize now—wait until spring.
• Monitor for fungal leaf spot; if spots spread, treat with copper spray.

The plant should recover and leaf out normally next spring.