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Control Powdery Mildew on plants and vegetables


August 1, 2022


Searles Gardening Team

What are Powdery Mildew symptoms?

Powdery mildew is one of the most commonly seen fungal problems in the backyard. It can affect a wide range of different plant species but is mostly first noticed on many members of the cucurbit tribe such as pumpkins and squash. Although fungal, powdery mildew is often spread by the natural habits of many sap sucking insects such as aphids and also underfoot by the yellow and black spotted ladybird that naturally feeds on the fungus.

What does Powdery Mildew look like?

Powdery mildew is easily spotted as distinct white markings on foliage that resemble freshly sprinkled talcum powder. In the case of cucurbits, it can appear equally on both stems and foliage of plants while on fruiting crops such as grapes, it can also be found smothering the fruit. Foliage quickly wither and die, even while holding and producing fruit (ie: Zucchini).

How to control Powdery Mildew

Good air flow is essential in and around plants and physical removal (while wearing gloves) of all affected foliage should be swift. Do not compost any plant material that is affected by fungal diseases, bagging or burning is suggested.  

Control powdery mildew by spraying with Searles Wettable Sulphur. Note: check the back of the label if this product is suitable for your plant type and mix only to the recommended dosage.