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Powdery Mildew in Connecticut

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Fungus

Active now in Connecticut

Powdery Mildew is currently active in Connecticut. Watch your susceptible trees closely and act early.

About Powdery Mildew

A widespread group of fungal diseases that produce a distinctive white powdery coating on leaves and shoots. It affects hundreds of tree, shrub, and plant species. Unlike most fungi, it thrives in warm, dry conditions with high humidity.

Symptoms to watch for

White to gray powdery coating on upper leaf surfaces and young shoots, leaf curling and distortion, stunted new growth, premature leaf drop in severe cases

Trees at risk in Connecticut

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Treatment options

Horticultural Oil or Neem Spray

Chemical TreatmentEffectiveness: MODERATE

Application of horticultural oil, neem oil, or potassium bicarbonate at first sign of infection. These contact treatments can prevent spore germination and reduce disease spread.

Improve Air Circulation and Site Selection

Cultural PracticeEffectiveness: MODERATE

Plant susceptible species in locations with good air movement and full sun. Avoid overhead irrigation. Select resistant cultivars when available.

Recommended Products & Tools

Helpful supplies for managing Powdery Mildew. Always read and follow label directions, and confirm a diagnosis before treating.

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Frequently asked questions

Is Powdery Mildew in Connecticut?

Powdery Mildew is currently active in Connecticut. Watch your susceptible trees closely and act early.

What does Powdery Mildew look like?

White to gray powdery coating on upper leaf surfaces and young shoots, leaf curling and distortion, stunted new growth, premature leaf drop in severe cases

What trees does Powdery Mildew affect in Connecticut?

It affects Red Oak, Flowering Dogwood, Common Lilac, Azalea, Crepe Myrtle. Susceptibility varies by species.

How do I treat Powdery Mildew?

Options include: Horticultural Oil or Neem Spray, Improve Air Circulation and Site Selection. Confirm the diagnosis before treating, and consider a certified arborist for high-value trees.