I have a herbaceous paeonia that does not flower. It is planted in a sunny well drained spot. The leaves are shrivelled with brown spots. Can you advise me please?
It these conditions are being met, and it is planted long enough to be well established, it may be suffering from disease, especially viruses.
It might be simply drought as the soil is very dry in places.
Mulch it with garden compost and give it another couple of years. Virus-affected plants cannot be cured.