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Rose powdery mildew

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Time to act

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Do Time to act in April

Do Time to act in May

Do Time to act in June

Do Time to act in July

Do Time to act in August

Do not Time to act in September

Do not Time to act in October

Do not Time to act in November

Do not Time to act in December

Rose powdery mildew is a fungus that produces airborne spores from infected stems or buds on roses. After overwintering on your plants, the disease is most likely to flare up if the roots are in dry soil and the leaves are in humid air – conditions that are often found when plants are grown near or against a wall.

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Symptoms

Leaves and buds on roses, possibly even stems and thorns, are covered by a dusting of white powder.

Find it on

roses – other powdery mildews affect other plants

Organic

Prune out and bin (don’t compost) infected leaves or stems. When buying roses, choose varieties with good resistance to powdery mildew – a reputable grower will be able to advise. Keep the soil around the roots moist at all times. When planting roses, prepare the soil well by digging in generous amounts of well-rotted compost or farmyard manure into the planting hole. For established roses, a thick layer of mulch around the base of the plant will help.

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Chemical

Before symptoms appear, apply a fungicide containing flutriafol at the recommended intervals from early spring.