What Is Powdery Mildew?
Powdery mildew is a common indoor fungus that affects plants. It causes leaves to turn yellow or brown and eventually die off. Its symptoms are similar to those of leaf spot, but it’s not just any leaf spot that’s affected by powdery mildew; it’s the plant itself! If left untreated, powdery mildew will kill your houseplants.
How Do You Treat Powdery Mildew?
There are two main ways to deal with powdery mildew: one involves using fungicides and the other involves treating the problem with milk. Fungicides are chemicals that kill fungi, while milk kills bacteria.
Both methods have their pros and cons, so which method would you choose?
Let’s take a look at both options.
Fungicides To Kill Powdery Mildew
The first option is to use fungicides. These include products like sulfur dioxide (SOD), copper sulfate, and pyrethrum. These chemicals kill fungi, but they don’t necessarily kill all of them.
Some fungi survive the chemical treatments and grow back within a few days after being exposed again. Other types of fungi may never die completely because they’re too hardy or resistant to these chemicals. Fungicides also may damage plants and won’t necessarily kill all of the powdery mildew.
Chemicals To Use Instead Of Fungicides
There are a few other ways to treat powdery mildew besides using fungicides. One option is to treat the infected area with milk or a milk product. This works because the bacteria that causes powdery mildew also can’t survive in an environment with a high concentration of calcium.
If you mix one tablespoon of milk into a quart of water, the solution will have a high enough concentration of calcium to slowly kill the powdery mildew. The infected leaves may turn brown, but that’s normal. Just be sure not to spray this on anything you’re going to eat!
Another option is to try baking soda. One teaspoon of baking soda mixed with one gallon of water should be enough to kill the powdery mildew on any houseplants.
General Powdery Mildew Facts
Powdery mildew likes warm, moist conditions. Don’t fertilize your plants if you suspect they’re infected, as this will only make the problem worse. Instead, opt for slow-release fertilizer.
This will ensure your plants always have access to nutrients without creating the perfect growing environment for powdery mildew. You should also water your plants early in the day so the leaves can dry before evening. Aim to water your plants until the soil is just evenly moistened, because soggy soil will only serve to promote more mildew.
Powdery mildew grows on all types of plants, including grass, trees, flowers, and vegetables. It loves hot, humid weather and will spread easily between plants in close proximity. If you have an infected plant, be sure to quarantine it immediately before the powdery mildew spreads to your other plants!
Hopefully, one of these methods will help you get rid of powdery mildew. If you have any other questions or concerns, don’t hesitate to ask us here at Doctor Dirt.
Jack is a web developer living in Buffalo, NY, and also works as a gardener to keep himself grounded. He writes about gardening and other assorted topics here.
Photo Credits: Kera / Pixabay, alexlmx / Pixabay
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