Hydrangea (Hydrangea macrophylla)

Botrytis storage mold: Bud rot. Proper ventilation during storage is important. Fungicide sprays before and/or during storage may be helpful.

Powdery mildew: White fuzzy patches on foliage.

Root rot (Pythium sp.): Stunted or wilting plants with root discoloration.

Virescence (phytoplasma): Green flowers or witches’-broom growth pattern. Destroy affected plants.