Troubleshooting
Herb Robert problems — and how to fix them
Herb Robert (Geranium robertianum) 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.
Powdery mildew
White powdery coating appears on leaves in hot, dry weather with poor air circulation. Improve spacing, avoid wetting foliage, and remove badly affected leaves; the plant usually recovers once conditions improve.
Self-seeding nuisance
Plants produce abundant seed that germinates readily across the garden. Deadhead promptly after flowering to limit spread, or hoe emerging seedlings on a dry day while still small.
Prevent herb robert problems before they start
Most herb robert issues are care-mismatch, not bad luck. Dial in the basics:
Herb Robert problems — FAQ
Why is my herb robert powdery mildew?
White powdery coating appears on leaves in hot, dry weather with poor air circulation. Improve spacing, avoid wetting foliage, and remove badly affected leaves; the plant usually recovers once conditions improve.
Why is my herb robert self-seeding nuisance?
Plants produce abundant seed that germinates readily across the garden. Deadhead promptly after flowering to limit spread, or hoe emerging seedlings on a dry day while still small.