Q: I planted ‘Snowflake’ oakleaf hydrangeas last December. They have done great this year. But about a week ago, I noticed that the leaves on two of the shrubs were wilting. I checked around the base and there was adequate moisture. Seven days later, the two plants have virtually given up. Is there anything that you could recommend?
A: My bet is on armillaria root rot.
This disease is not all that common but it causes RAPID death of oakleaf hydrangeas. In my experience, this root rot is associated with excess moisture. Might you have loved your hydrangeas to death with a water hose?
No fungicide can cure the disease….but if you really love ‘Snowflake’, re-amend the soil with mini-pine-bark nuggets to increase drainage and plant two more this fall.
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