Hydrangeas – Frost Damage
Q: I planted 9 ‘Annabelle’ Hydrangeas in March in an area on the North side of the house that receives almost no sun. The soil had a lot of clay so I amended with peat moss, composted manure and sand.
I watered well and this past weekend we received a LOT of rain. They were looking great. This morning I noticed some black spots on some of the leaves and some of the newest growth had turned to mush and fallen over.
A: Theresa Schrum replies: “This actually sounds more like frost damage than a fungus problem, although it could be the latter. We had some hard frosts right after you planted your shrubs and the new foliage may have been damaged.
Frost damaged hydrangea foliage turns to black mush, just as you described. My advice is to wait. If the new foliage that emerges from this point on does the same thing (if we don’t get any more frosts), then it must be an early fungus.”