Troubleshooting
Smooth Solomon's Seal problems — and how to fix them
Smooth Solomon's Seal (Polygonatum biflorum) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Solomon's seal sawfly (Phymatocera aterrima)
Grey-green larvae strip leaves to the midrib in late spring and early summer; inspect stems regularly from late May onwards and remove larvae by hand or treat with a contact insecticide.
Powdery mildew
In dry, warm summers, powdery mildew can coat the upper leaf surface with white powder; improve air circulation, maintain soil moisture, and remove badly affected foliage.
Prevent smooth solomon's seal problems before they start
Most smooth solomon's seal issues are care-mismatch, not bad luck. Dial in the basics:
Smooth Solomon's Seal problems — FAQ
Why is my smooth solomon's seal solomon's seal sawfly (phymatocera aterrima)?
Grey-green larvae strip leaves to the midrib in late spring and early summer; inspect stems regularly from late May onwards and remove larvae by hand or treat with a contact insecticide.
Why is my smooth solomon's seal powdery mildew?
In dry, warm summers, powdery mildew can coat the upper leaf surface with white powder; improve air circulation, maintain soil moisture, and remove badly affected foliage.