Saving Thuja (Arborvitae) from Drought and Spider Mites

After a hot, dry summer, two three-year-old thuja trees are browning from bottom to top. Fear of spread to a 7-foot hedge.

Two Primary Culprits

Spider mites: Shake a branch over white paper; moving specks confirm mites. Treat with Ferti-lome Triple Action Plus.
Drought: The dominant issue. Water deeply (slow drip for ~1 hour per tree) weekly, plus a mid-week soak if restrictions allow.

Thuja are hardy. With consistent deep watering, they may leaf out next spring. Full recovery takes months. Prioritize water now.

Plant Diseases: Pomegranate Orchard Decline: Root/Trunk Rot from Poor Drainage; Hemlock Decline from Ground Up: Woolly Adelgid Likely; Topping Delays Inevitable; Thuja (Arborvitae) Browning After Planting: Transplant Shock or Water Stress?; Oak Decline After Paving: Root Damage and Recovery Plan; Pine Trees Browning While Neighbors Stay Green: Site-Specific Stress; Plum Tree Wilt: Lasiodiplodia Fungus and Extension Resource; Dying Poplar Trees: Cytospora Canker Diagnosis and Management; Dying Poplar After Root Damage from Retaining Wall Construction; Arborvitae Hedge Dieback and Spruce Galls: Comprehensive Causes; Sudden Oak Death and Ash Tree Decline in Ohio

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