Q What are the symptoms of oriental poppy downy mildew?
A Typically, pale or yellow spots or angular blotches appear on the upper leaf surface, which then darken as the infection progresses. Underneath, a light grey or purplish fungal growth, which is downy-like in appearance, can often be seen. Affected leaves and stems become distorted, hindering flower development, plants lose their natural vigour and eventually collapse. It's most common in in warm, damp seasons, so continued vigilance is necessary. Learn to spot the early symptoms, so that control measures can be implemented.
Caption: Downy mildew can prevent oriental poppies flowering
Q How can I control oriental poppy downy mildew?
A This can be difficult, particularly in warm, damp weather, but avoiding overhead watering helps. Ideally, water early in the day so that leaves can dry before nightfall. Clear away any decaying plant debris or infected plant material promptly. Propagation by root cuttings rather than seed or division may also help. Fungicides containing trifloxystrobin may also give some control if applied promptly.
Q When was oriental poppy downy mildew first seen in the UK?
A Oriental poppy downy mildew (sometimes referred to as oriental poppy pseudo mildew) is not a new disease – it was first recorded in the UK on Papaver dubium in 1883!
It’s quite common and often seen during warm, damp seasons, particularly in dense border plantings. It's not confined to any region or locality.