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Natural Ways to Get Rid of Powdery Mildew on Plants

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13 Natural Ways to Get Rid of Powdery Mildew on Plants

It may start as just a few unsightly leaves, covered in gray or white powdery patches or spots. Left unchecked, powdery mildew will spread to other plants, especially in warm, dry weather [1].

It will weaken plants and cause the leaves to curl up, twist, or dry out. This type of fungal disease can affect fruit trees, vegetable crops, and plants in your flower garden.

Here’s how to get rid of powdery mildew naturally.

1. Baking soda

This is sodium bicarbonate, although you can also use potassium bicarbonate to kill powdery mildew spores. Both remedies can effectively control the disease.

Make a homemade powdery mildew spray using baking soda. For the recipe, combine one tablespoon of baking soda and half a teaspoon of pure castile soap in a gallon of water.

Shake well and thoroughly spray the underside of the leaves and stems. You can also apply it to the soil surface around the base of plants.

Use as a preventative measure or at the earliest signs of the disease.

2. Vinegar

Organic gardeners often use vinegar mixture as an anti-fungal treatment for plants.

The acetic acid in it makes it effective in killing powdery mildew. However, the solution needs to be fairly weak so as not to burn plant leaves.

ACV is the preferred choice. To use apple cider vinegar for powdery mildew, mix 3 tablespoons to a gallon of water. Spray plants liberally.

3. Neem Oil

This oil has been used for generations by gardeners as a natural insecticide and fungicide.

To use neem oil for powdery mildew, combine 3 tablespoons of the oil with one teaspoon of liquid soap in a gallon of water. Next, add to a spray container and spray leaves to kill the fungus spores.

Alternatively, you can purchase neem oil concentrate that is ready-to-use.

To avoid leaf burn, use the solution early in the morning or in the evening. Moreover, this is a good organic choice that will not harm beneficial insects and wildlife in the garden.

4. Improve Air Circulation

To reduce the spread of the disease, give plants move room to breathe. Pruning and thinning out if necessary will prevent overcrowding; thus, providing adequate air circulation.

5. Avoid Overhead Watering

Fighting some powdery mildew is not helped by overhead watering or getting the leaves wet. This increases the risk of dampness and humidity that will encourage mildew growth [2].

6. Insecticidal Soap

Using a soapy solution to rid the garden of pests and diseases is nothing new. Moreover, you can get it as a ready-to-use spray.

Brands such as Bonide carry insecticidal soap containing the active ingredients of potassium salts of fatty acids and Spinosad. It is effective against powdery mildew as well as pests.

Spray it directly onto the fungus at 7-day intervals.

7. Cueva

This commercial product contains copper, another age-old garden remedy used to control fungal and bacterial diseases organically.

Cueva is a flowable liquid copper fungicide that works against powdery mildew, bacterial cankers, anthracnose, brown rot, and more.

The product penetrates the cells of the disease, causing fatal cell leakage. Moreover, Cueva is OMRI-Listed for safe use on organic crops.

8. Bonide Liquid Copper Fungicide

This is another natural copper formulation powdery mildew fungicide. It is also effective in treating rust on plants and downy mildew.

Moreover, the product is safe to use in your organic garden. Furthermore, all kinds of ornamental, vegetable crops and fruit trees can benefit from this ready-to-use Bonide LCF spray.

9. Banish

Banish is a popular and powerful all-natural organic fungicide containing Geraniol, an oil extract present in geranium.

The product works to prevent mildew growth by disrupting spore germination and mycelium growth, ultimately destroying the pathogen cell.

However, it is very potent, so use it according to the instructions that come with your purchase.

10. Milk

This is a strange remedy and one not yet fully explained scientifically. However, many gardeners find that it works.

To get rid of powdery mildew with milk, make up a mixture of milk and water (40/60 ratio). Next, remove all affected leaves before applying the spray.

Afterward, spray the solution onto your plants, covering all surfaces. Repeat after 10-14 days and after a heavy rain shower.

This milk treatment works great on pumpkins, cucumbers, and other plants susceptible to this plant disease.

11. Garlic

Here is another natural remedy for powdery mildew that you can find in the kitchen. Garlic contains significant amounts of sulfur which is an effective powdery mildew treatment.

For this, blend 2 bulbs of garlic in two cups of water. Next, strain the mixture and add in one teaspoon of liquid soap. Finally, use it as a foliar spray by diluting a quarter cup of the garlic mixture in a gallon of water.

A far easier option is to purchase a product containing garlic that fights against this and other common fungal diseases.

12. Compost Tea

Compost tea has anti-fungal properties. To make a simple compost tea for plants, add some organic compost to a bucket of water.

Leave it to steep for a while and then use the solution to water plants. This method will help improve the soil and strengthen plants against diseases.

13. Pruning

Cutting back plants to let in more air is sometimes not enough to control mildew.

Prune small trees and shrubs that are cutting off the air supply and trim off any dead or diseased leaves/plant parts to maintain disease-free plants.


Mildews are an unwelcome common sight in even the best-kept gardens. Fortunately, there are plenty of home remedies and natural ways to prevent them from ruining your plants.

Picture via commons.wikimedia.org

Andre Campbell

Organic farmer and co-founder of Dre Campbell Farm. He appreciates everything in nature -- sunshine, plants, animals, and human life.

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