How to Prevent Powdery Mildew on Plants Using Baking Soda - Backyard Boss
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How to Prevent Powdery Mildew on Plants Using Baking Soda

Have you ever seen a plant covered in a white, powdery substance and wondered what it was? Chances are, you were looking at powdery mildew. Powdery mildew is a fungus that can affect many plants and, if left untreated, can cause severe damage.

But don’t worry — there are steps you can take to prevent this disease from developing in the first place. One of the easiest is to use baking soda. Learn more about how to use baking soda to prevent powdery mildew on plants below!

What You’ll Need:

spade with pile of baking soda
Image credits: FotoHelin via Canva

This method requires little ingredients that you probably already have laying around your kitchen.

  • Baking soda
  • Mild liquid dish soap
  • Water
  • Clean spray bottle

Prevent and Control Powdery Mildew On Plants Using Baking Soda

Close up of cucumber leafs with white powdery mildew. Plant disease
Image credits: matahiasek via Shutterstock

Powdery mildew is a common problems that gardeners face. It looks like a white or gray powder on the leaves and stems of plants. This nuisance can cause the leaves to turn yellow or brown and eventually drop off.

The fungus can also affect the plant’s fruit, causing it to rot. One of the best ways to prevent, treat, and control powdery mildew is to use baking soda. Here’s how:

Step One – Mix Your Ingredients

Mix one tablespoon baking soda, half a teaspoon mild liquid dish soap, and one gallon of water. Pour into your clean spray bottle.

Step Two – Spray

Spray the mixture onto affected plants and coat all leaf surfaces evenly. Cover both the tops and undersides of the leaves and stems. It is best to spray your plants in the early morning to avoid sunscald.

Step Three – Repeat

If you already have powdery mildew on your plants, repeat this treatment every seven days until the fungus is gone. If this is for preventative means, spray liberally every two weeks.

Why This Method Works 

Powdery Mildew Tomato
Image credits: Taew Jari via Shutterstock

Powdery mildew is a fungus in a group of fungi called Erysiphaceae. It can affect a wide range of plants, from fruits and vegetables to ornamental flowers. This fungus thrives in warm, humid conditions, so it’s widespread in late summer and early fall. While it isn’t usually deadly to plants, it can cause them to become stunted and produce less fruit.

Baking soda works to prevent and treat powdery mildew because it changes the pH of the plant’s surface. When applied to the leaves of a plant affected by this disease, baking soda will raise the pH and make it harder for the fungus to grow.

Baking soda is most effective when used as a preventative measure before the fungus has had a chance to take hold. Once powdery mildew has already started to grow, baking soda can still treat it effectively, but it may need to be used more frequently.

Other Methods To Prevent This Fungus

Powdery Mildew on a tomato plant
Image credits: Taew Jari via Shutterstock

Baking soda is an inexpensive and easy way to prevent and treat powdery mildew. But plenty of other natural ways to rid your plants of this disease!

Air Circulation

One of the simplest ways to prevent powdery mildew is to increase air circulation around your plants. This can be done by spacing them further apart or using fans to create a breeze.

Watering and Feeding

It’s also important to keep your plants healthy and stress-free. This means giving them plenty of water and nutrients and avoiding any damage that could open up the plant’s surface and make it more vulnerable to infection.

Keep Them On The Dry Side

If you live in an area with a lot of humidity, you may also want to consider using a dehumidifier. This will help keep the air around your plants dry, preventing this fungus from taking hold.

Other Treatments

Several products are available that can be used as preventive treatments. These include horticultural oils, neem oil, milk spray, and sulfur-based sprays.

Avoid Overhead Watering

Overhead watering is one of the most common ways that fungal diseases spread. When water droplets land on infected leaves, they can splash spores onto healthy leaves nearby. To prevent this, water your plants at the base instead of above. If you must water from above, do so early in the day, so the leaves have time to dry off before nightfall.

Plant Resistant Varieties

One of the best ways to prevent powdery mildew is to grow resistant varieties of plants. Many different plant species have been bred to be resistant to this disease. When choosing plants for your garden, look for types that are labeled as “powdery mildew resistant.”

Following these tips can dramatically reduce the risk of powdery mildew taking hold in your garden. Remember, an ounce of prevention is worth a pound of cure!

Happy and Disease Free

So, there you have it — a simple and easy way to prevent powdery mildew from developing on your plants using baking soda. Plus, some additional ideas to improve your chances of never dealing with this annoying fungus!

Do you have any tips or tricks of your own? Post them in the comments below! And be sure to share this article with your friends and family who also love gardening. Thanks for reading!