Oakleaf Hydrangea Sudden Death: Likely Armillaria Root Rot from Overwatering

Rapid wilting and death in 'Snowflake' oakleaf hydrangea = classic Armillaria root rot. Trigger: excess moisture.

Diagnosis

No fungicide cures it. If you overwatered ("loved it to death"), that's the cause.

Replanting Strategy

• Amend soil heavily with mini pine bark nuggets for drainage.
• Replant in fall.
• Water only when soil is dry 2 inches down.