Treating powdery mildew on plants

Photo Credit: The Spruce

When it comes to start garden, it is good to be aware of some of the problems that can arise. Powdery mildew is one of the most common problems and easily recognized plant diseases when planting vegetables, herbs and flowers. Almost no type of plant is immune from powdery mildew. However, some plants are more susceptible to the problem than others. ​Plants such as lilacs, phlox, crab apples, monarda, grapes, roses, squash, and cucumbers are all likely targets for powdery mildew. To recognize powdery mildew, as the name implies, it looks like powdery splotches of either white or gray, on the leaves and the stems of the plants in your garden. There are several types of powdery mildew fungi, but all of these look the same. You may not notice a problem on your plants until the top surfaces of the leaves turn powdery, but the powdery mildew can also affect the lower leaf surface, the stems, flowers, the buds and even the fruit of the plant. Although powdery mildew is quite unattractive, powdery mildew is rarely fatal. However, powdery mildew does stress the plant and severe or repetitive infections of powdery mildew will also weaken the plant. If enough of the plant leaf surface becomes covered with the powdery mildew, photosynthesis is also impaired. Infected leaves of a plant infected by powdery mildew often fall prematurely. This can be a particular a problem on edible crops because there is insufficient photosynthesis which can diminish the flavor of the fruit or vegetable. If the buds become infected with the powdery mildew, they may not open and mature at all.

Powdery mildew fungi are host specific, which means the different powdery mildew fungi will infect different plants. The powdery mildew on your lilac plants will not spread to your grapes or your roses. However all of the powdery mildews favor the same sort of conditions. Powdery mildew fungi seem to be everywhere. They overwinter in plant debris which can begin producing spores in the spring. These mildew spores are carried to your plants via wind, splashing water and insects. Conditions that encourage the growth and the spread of powdery mildew can include dampness or high humidity which is not common during rainy seasons or in extreme heat, crowded plantings, poor air circulation. To control powdery mildew when planting vegetables you want to choose healthy plants and keep them growing healthy. You want to find a powdery mildew-resistant cultivar, if your area is more susceptible, and don't plant non-resistant varieties in the shade. If your plants do become infected with powdery mildew, you can start by removing and destroying all of the infected plant parts, improve the air circulation by thinning and pruning. Don't fertilize until the problem is corrected.

Powdery mildew is a problem that favors young, succulent growth. Don't water your plants from above. To get rid of powdery mildew you can apply a fungicide. Look for ingredients to include potassium bicarbonate, sulfur, neem oil, or copper. A home remedy and DIY idea for powdery mildew can be made from baking soda which is also an effective preventative. One diy idea from milk is useful for helping to prevent and cure powdery mildew. For continuous protection from powdery mildew, most fungicides will need repeat applications every seven to fourteen days. Always follow the label instructions for both the application and waiting period before harvest.

You will find these DIY ideas for treating powdery mildew on plants on The Spruce site. On the site, you will find DIY ideas, recipe ideas, decor, gardening ideas, craft ideas, planting vegetables, start garden and more. **

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