Troubleshooting
Hardy Geranium 'Rozanne' problems — and how to fix them
Hardy Geranium 'Rozanne' (Geranium 'Rozanne') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Mid-season sprawl and bare centre
After the first flush the mound can open up and look tired. Shear the whole plant back by about a third in midsummer to trigger a fresh, compact flush of foliage and flower.
Reduced flowering in shade
Too little light thins blooms and stretches stems. Move to a sunnier spot or accept fewer flowers; in hot climates some afternoon shade is a worthwhile trade-off.
Powdery mildew
Occasional white coating in dry, crowded or stressed plants. Improve airflow, keep moisture steady at the roots, and cut back affected growth to reflush clean leaves.
Vine weevil in containers
Larvae chew roots of potted plants, causing sudden collapse. Check rootballs when repotting, use fresh compost, and treat pots with biological nematodes if grubs appear.
Prevent hardy geranium 'rozanne' problems before they start
Most hardy geranium 'rozanne' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for hardy geranium 'rozanne' in general rather than its problems? Read the full hardy geranium 'rozanne' care guide — light, water, soil and feeding.
Hardy Geranium 'Rozanne' problems — FAQ
Why is my hardy geranium 'rozanne' mid-season sprawl and bare centre?
After the first flush the mound can open up and look tired. Shear the whole plant back by about a third in midsummer to trigger a fresh, compact flush of foliage and flower.
Why is my hardy geranium 'rozanne' reduced flowering in shade?
Too little light thins blooms and stretches stems. Move to a sunnier spot or accept fewer flowers; in hot climates some afternoon shade is a worthwhile trade-off.
Why is my hardy geranium 'rozanne' powdery mildew?
Occasional white coating in dry, crowded or stressed plants. Improve airflow, keep moisture steady at the roots, and cut back affected growth to reflush clean leaves.
Why is my hardy geranium 'rozanne' vine weevil in containers?
Larvae chew roots of potted plants, causing sudden collapse. Check rootballs when repotting, use fresh compost, and treat pots with biological nematodes if grubs appear.