How to Control Powdery Mildew in the Garden

Powdery mildew is a common fungal disease that affects most garden plants, this disease can prove fatal and negatively impact the appearance of some plant species and cause significant damage reducing fruit production in the tomato plant and resulting in death if the disease persists. Favorable environmental factors influence powdery mildew such as humid, moist, and damp conditions.

Extended periods of long dry climates followed by cool nights and poor cultural practices for example installing plants too closely that encourage poor air circulation, and not providing sun-loving plants with adequate lighting. As we continue the discussion we will go more in-depth including how to treat powdery mildew along with taking preventive steps to discourage this disease.

Symptoms of Powdery Mildew

• White patches of fungal growth appear or develop on the lower surface of the leaf, if this issue is allowed to persist can cover the entire leaf.
• Purple to reddish blotches may also develop on leaves.
• The plant’s tissues can sometimes become distorted.
• Yellow leaves will become visible.
• The leaves’ edges curl upwards exposing the white Powdery fungal growth.
• Fallen leaves
• Black fungal structures that are small and round may also be visible on the leaves undersides

Powdery mildew can affect not only the leaves but also flowers, fruit, fruit stalks, petioles, and calyxes

 How to Prevent Powdery

• Provide proper air circulation by avoiding crowded plants, and giving plants their proper spacing.
• Avoid overhead irrigation.
• Make sure that your plants get the right amount of sunlight.
• Choose resistant plants.
• Don’t use infected tools on healthy plants, after each pruning procedure pruners, loppers, pruning saws, and knives should be sterilized with a solution of bleach and water.
• When growing plants in greenhouses ensure there is good ventilation.
• Areas where plants are grown indoors should be well-ventilated.

How to Treat Powdery

• Remove infected plant parts.
• Apply fungicide according to the manufacturer’s directions for the best results.
• Prune dense plants to improve air circulation.
• Avoid overhead irrigation.
• Don’t fertilize infected plants until powdery mildew is brought under control because fertilizer application will encourage new growth that’s susceptible to powdery mildew.
• Don’t plant susceptible plant varieties in the shade.
• Giving Infected plants a daily washing will disrupt the spore’s cycle.
• The application of neem oil proves to be effective provided is applied at the first sign of powdery mildew.
• Potassium bicarbonate used as a fungicide will give good results, mix 1 tablespoon of potassium bicarbonate and 1/2 teaspoon of liquid soap in 1 gallon of water. Add this solution to a 32 oz spray bottle and use as the need arises.

Homemade Remedies to Treat Powdery Mildew

• Here is how to mix. dissolve 1 teaspoon of baking soda into 1 quart of water, and add a few drops of liquid soap or insecticidal soap to help the solution stick and spread to the leaves. Ivory liquid soap is ideal.  Mix thoroughly, and then pour it into a 32 oz spray bottle and apply to infected plant parts.
• Mouthwash has a positive effect when treating powdery mildew, mix one part ethanol-based mouthwash with three parts water. Add to a 32 oz spray bottle and apply to infected areas.
• Vinegar can also help to reduce the spread of powdery mildew, to make this solution mix 2-3 tablespoons of apple cider vinegar with a gallon of water, making sure that the apple cider vinegar contains 5% acetic acid. Place this solution in a 32 oz spray bottle and apply to infected areas be mindful however that too much apple cider vinegar can burn plants so be careful when applying.
• Milk is another homemade remedy that can get the job done, simply mix % 40 milk with % 60 water.  Apply this mixture to the plant leaves every 10-14 days as a preventive meassure.

Plants that are Resistant to Powdery Mildew

Installing these garden plants will save you the trouble of having to deal with powdery mildew.

• Mountain Gordlinia.
• Garden Phlox.
• HFuji Waterfall Hydrangea,
• Itoh Peony.
• Wild Pansy.
• Profusion Zinnias.
• Largeleaf Phlox.
• Purple Coneflower.
• Kousa Dogwood.
• Blue Star Juniper.

Plants that are most Susceptible to Powdery Mildew

These are just a list of a few plants that are susceptible to powdery mildew.

• Peppers
• Lettuce
• Grapes
• Cucumbers
• Peppers
• Zucchini
• Pumpkins
• Squash
• Potatoes
• Melons
• Parsley
• Chrysanthemums
• Begonias
• Zinnias
• Dahlias
• Sunflowers
• Roses

Additional information

Infected plant parts that are removed should not be tossed into the compost bin but sealed in a garbage bag and properly disposed of.

Conclusion

Powdery Mildew can be controlled or prevented by the use of good cultural practices,  or by the installation of resistant varieties. This fungal disease can do damage to plant life if allowed to persist, if your garden plants are showing signs that are discussed it may be that you’re facing a powdery mildew issue. Quick action on your part should take place to ensure the continued health of your garden plants.