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The short answer is yes. But let me elaborate! Fighting the ghostly dusting of powdery mildew on plants is a common battle for gardeners. This fungal disease, caused by various species of ascomycete fungi, is easily recognizable by the white to grayish, talcum-powder-like spots it leaves on a wide array of plant species. Thriving what seems like all climates, including ours, powdery mildew can mar the beauty of ornamentals and hinder the growth of edibles.

Fortunately, combating powdery mildew doesn’t have to involve harsh chemicals. Research from Cornell University offers an organic remedy involving baking soda, a household staple. By dissolving 1 tablespoon of baking soda in a gallon of water and adding a teaspoon of neem oil as a sticking agent, gardeners can create an effective deterrent. Spraying this solution at the first sign of the disease and continuing applications every 7 to 10 days throughout the season can help keep plants healthy.

Plant selection plays a crucial role in managing powdery mildew. Opting for resistant varieties can provide an inherent defense against the disease. And while succulent tissue is more prone to infection, it’s not just ornamental plants like roses and hydrangea that suffer! Vegetables like squash and okra are also vulnerable. To curb the disease’s spread, it’s advisable to forgo late-summer nitrogen fertilization, which promotes the growth of susceptible succulent tissue.

Cultural practices are also part of the organic arsenal against powdery mildew. Good garden hygiene, such as removing and destroying all infected plant parts, is essential. However, these should never be composted, as typical compost temperatures may not be sufficient to kill the fungus. Additionally, enhancing air circulation through selective pruning and avoiding overhead watering can keep humidity levels in check, reducing the chances of infection. But often the rain schedule has other ideas about humidity levels and mildew can sneak up on your garden despite best practices.

In cases where powdery mildew becomes a persistent problem, turning to organic chemicals like sodium bicarbonate or sulfur can offer relief. Neem oil, an extract from the neem tree, also serves as an organic option, although it is crucial to use it judiciously, as with any treatment. When an outbreak becomes severe, and all organic methods are exhausted, gardeners may often turn to conventional fungicides as a last resort.

Ultimately, the best strategy against powdery mildew is early detection and consistent management. By integrating a variety of organic practices and being vigilant about plant care, gardeners can ensure their green sanctuaries remain both lush and healthy.

If you want to see a battle against powdery mildew in action, feel free to swing by The Gathering Garden in Mount Gilead at the corner of W Allenton St and School St, if you want to discuss gardening with us, you can find out more about or workdays on our facebook page.

In these weekly columns, I will share the science of gardening and so many more interesting tidbits. Check back here every week for tailored Montgomery County garden advice, sharing our garden updates, and more.

Let’s grow together!

This article was originally published in the Montgomery Herald and is reused here with permission by Mary Poplin.