Troubleshooting
Common peony problems — and how to fix them
Common peony (Paeonia officinalis) 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.
Botrytis blight (grey mould)
Botrytis paeoniae causes blackened buds, wilting shoots, and grey fuzzy spore masses at the base. Remove affected material promptly, improve air circulation, and avoid wetting foliage. Fungicide (copper-based or thiophanate-methyl) applied at bud swell can help in recurring cases.
Failure to flower
The most common cause is planting the crown too deep — eyes must be no more than 2–5 cm below the soil surface. Other causes include insufficient sun (under 6 hours), over-fertilisation with nitrogen, or the plant being too young (blooms reliably from year 2–3 onward).
Powdery mildew
A white powdery coating on leaves appears in late summer, especially during warm days and cool nights. Improve airflow, avoid water stress, and remove badly affected foliage. Treat with a sulfur-based or potassium bicarbonate fungicide if severe.
Prevent common peony problems before they start
Most common peony issues are care-mismatch, not bad luck. Dial in the basics:
Looking for common peony in general rather than its problems? Read the full common peony care guide — light, water, soil and feeding.
Common peony problems — FAQ
Why is my common peony botrytis blight (grey mould)?
Botrytis paeoniae causes blackened buds, wilting shoots, and grey fuzzy spore masses at the base. Remove affected material promptly, improve air circulation, and avoid wetting foliage. Fungicide (copper-based or thiophanate-methyl) applied at bud swell can help in recurring cases.
Why is my common peony failure to flower?
The most common cause is planting the crown too deep — eyes must be no more than 2–5 cm below the soil surface. Other causes include insufficient sun (under 6 hours), over-fertilisation with nitrogen, or the plant being too young (blooms reliably from year 2–3 onward).
Why is my common peony powdery mildew?
A white powdery coating on leaves appears in late summer, especially during warm days and cool nights. Improve airflow, avoid water stress, and remove badly affected foliage. Treat with a sulfur-based or potassium bicarbonate fungicide if severe.