Copper ions are toxic to fungi and bacteria because they destroy proteins in fungal tissues. Copper is a very effective fungicide, but it is very important to follow label directions closely. Powdery mildew fungus favours high humidity and dry conditions. Copper is a metal that, in dissolved form, penetrates plant tissues and helps control fungal diseases such as: Powdery mildew; Downy mildew; Septoria leaf spot; Anthracnose; Black spot; Fire blight; That said, its effectiveness is limited against late blight of potatoes and tomatoes. Water splash and air currents spread the spores of powdery mildew which grows on the surface of the leaf only. There is a large number of diseases you can control with the Scott lawn fungicide, including brown patch, powdery mildew, yellow patch, gray & pink snow mold, pythium, red thread, leaf spot, and spring dead spot. Myclobutanil, propiconazole, and thiophanate-methyl have systemic properties and can be sprayed less often than chlorothalonil, sulfur or copper-based fungicides. Copper Fungicides: When formulations of copper are dissolved in water, copper ions are released into solution. Too much copper will be detrimental to the plant and the soil. What is Copper Fungicide? However, resistance management is a concern. Powdery mildew is a fungus which spreads a white or ash-grey film over the upper and lower surfaces of the leaves of plants-usually the older leaves. Blue Shield is a well-established copper hydroxide fungicide for the protection of dozens of fruit, nut and vegetable crops against many different fungal infections. The main drawback of copper fungicides is the potential for severe injury to grape foliage, depending on variety and weather conditions, and for reduced vine vigor and yields even in the … Just as a few examples, Blue Shield protects against black rot, peppery leaf spot, ring spot and downy mildew in brassicas; black spot in apples, pears and citrus fruit; and anthracnose and bacterial black spot in mangoes. However, because copper can also kill plant tissue, there is a risk of injuring foliage. Copper Fungicides. It is recommended that the most effective products are applied when symptoms are first observed (one powdery mildew spot on 45 to 50 leaves) and then later in the season when switching to a protectant spray program rather than the reverse. Fungicides work best as preventatives rather than cures, so if you notice your plants starting to turn white, grey or brown, take action! c Fixed copper compounds that are registered for use on grapes include Kocide 101, BCS-Copper Fungicide, Ten-Cop 5E, copper oxychloride sulfate (C-O-C-S), and many other compounds and formulations. Warning. Ensure that plants are well-watered before applying and don't apply during daylight hours. Some ingredients, such as vinegar and baking soda, can cause sunburn to your plants. In the long-run, this will reduce … When powdery mildew persists and sprays are repeated, it is recommended to rotate (alternate) fungicides to decrease the chance of fungi developing resistance. Fungicides are an important tool for managing powdery mildew in-season.