Buzz
Powdery mildew is a fungal disease that appears as a powdery white coating on plants, typically forming circular spots. This condition usually affects the leaves but can also spread to stems, flowers, and fruits. Infected leaves may become curled, cracked, yellowed, and dry out. To treat powdery mildew, you will need to apply a fungicide. Fortunately, organic fungicides can be easily prepared at home. Additionally, preventive measures should be taken to stop the disease from returning.
Steps
Making Homemade Fungicide Spray
Try mixing baking soda, vegetable oil, and dish soap with water. Baking soda is a traditional organic solution for fighting fungus. To effectively treat fungus on plants, you need to add oil and soap to help the baking soda adhere to the leaves. Combine 1 tablespoon (15 g) of baking soda with 1 tablespoon (15 ml) of vegetable oil and 1 teaspoon (5 ml) of dish soap with 4 liters of water.
- Mix the ingredients well and pour the solution into a clean spray bottle.
- You can also use oil-based soap, such as Murphy’s Oil Soap, as a substitute for the dish soap and oil. Simply use 2 tablespoons (30 ml) of oil-based soap and 4 tablespoons (60 g) of baking soda mixed with 4 liters of water.
- Consider using potassium bicarbonate as an alternative to baking soda. Potassium bicarbonate may be less harsh but just as effective when used on plants.
Pha dung dịch giấm. Pha 2- 3 thìa canh (30 ml - 45 ml) giấm trắng hoặc giấm táo với 4 lít nước. Rót dung dịch vào bình xịt sạch.
- Không dùng lượng giấm nhiều hơn trong công thức trên, vì nồng độ giấm quá đậm đặc có thể làm cháy cây. Nhớ xịt thử dung dịch lên một phần nhỏ của cây trước khi phun lên toàn bộ các lá cây nhiễm bệnh.
Thử dùng dung dịch dầu neem. Dầu của cây neem nổi tiếng với công dụng trừ sâu và diệt nấm. Pha 1 thìa cà phê (5 ml) dầu neem và 0,5 thìa cà phê (2,5 ml) xà phòng rửa bát với 1 lít nước. Rót dung dịch vào bình xịt sạch để sử dụng.
- Dầu neem có bán ở các cửa hàng thực phẩm chăm sóc sức khoẻ, một số cửa hàng gia dụng và trên mạng.
Thử dùng sữa pha với nước. Đáng ngạc nhiên là sữa cũng có đặc tính kháng nấm và rất công hiệu trong việc trị bệnh phấn trắng. Thử pha 350 ml sữa vời 850 ml nước và rót vào bình xịt sạch.
- Sữa tách béo hay nguyên kem đều dùng được, vì thành phần có đặc tính diệt nấm là protein chứ không phải chất béo.
Pha dung dịch tỏi và nước. Cho 2 củ tỏi bóc vỏ vào cối xay sinh tố và rót thêm 1 lít nước vào. Bật máy xay ở tốc độ cao khoảng 5-10 phút. Lọc hỗn hợp qua vải thưa và pha loãng từng mẻ đủ dùng với tỷ lệ 1 phần dung dịch tỏi với 9 phần nước trong bình xịt.
- Bảo quản dung dịch tỏi đậm đặc trong tủ lạnh có ghi nhãn cho đến khi cần dùng.
Sử dụng thuốc xịt đúng cách
Test each spray on a small area of the plant before full application. Sometimes, fungicides can burn or damage plant leaves. Test each product on a small section of the plant, such as a leaf at the bottom, before spraying the entire plant. Apply enough of the solution so that it runs off and allow it to dry.
- If the leaves begin to yellow or brown, the solution may be too strong for the plant. Try a different spray on other leaves until you find two that work effectively.
Alternate between two types of sprays to prevent mildew from developing resistance. Once you’ve found two effective treatments, alternate between these sprays to prevent the powdery mildew from developing resistance to any one solution.
- For example, you could use a baking soda solution one week and a milk or vinegar solution the following week.
Spray infected areas of the plant in the morning, no more than once a week. When starting your powdery mildew treatment regimen, spray in the morning so that sunlight helps dry the solution on the leaves. Typically, you’ll notice improvement after just one treatment.
- Wait at least one week before applying another treatment, and only do so if you haven’t seen any improvement in the leaves after the first round of spraying.
Wipe the leaves with a clean cloth to remove some of the powdery mildew. Before applying the solution to infected leaves, use a dry, clean cloth to wipe off some of the powdery mildew from the plant. This step helps reduce the amount of mildew that will wash off with the solution and into the soil.
- You can also rub the leaves together to remove excess powdery mildew.
Allow the solution to run off the leaves. When using your homemade solution, spray each affected leaf with enough liquid to cause it to run off the edge of the leaf. Don’t wipe the solution dry—just let it drip off and dry naturally.
Use chemical fungicides with caution. While chemical fungicides can be effective, they may also cause other issues in your garden. These chemicals can harm beneficial microorganisms in the soil, as well as bees and insects that aid in pollination—vital creatures for a thriving garden. Chemical products can also affect the safety of the fruits and vegetables you consume, so be sure to follow the instructions on the label when using them on edible plants.
- Since organic fungicides are easy to make at home, consider trying these before resorting to chemical fungicides.
Controlling and Preventing Powdery Mildew
Remove infected lower leaves to reduce the spread of mildew. If you catch powdery mildew early, you can prevent its spread by removing the affected leaves. Do not place these leaves in the compost bin, as the mildew could spread through the compost and infect other plants.
- Dispose of the infected leaves in the trash to prevent the fungus from spreading.
- Removing the infected leaves can also help prevent the disease from reaching other plants, which is especially important if you grow leafy vegetables.
Ensure proper airflow around the plants. Powdery mildew thrives in humid environments. Try to space out your plants in the garden to allow air to circulate freely. If possible, use a fan to improve airflow around plants during hot, humid days.
- If your plants are infected with mildew indoors, move them outdoors to a sunny spot during the summer. Fresh outdoor air can reduce the risk of reinfection by the fungus.
Provide adequate sunlight for your plants. Too much shade can prevent the leaves from drying properly after rain or watering. The right amount of sunlight helps strengthen plants, making them less susceptible to diseases. Plant according to each plant's specific light requirements.
- If you live in a region with frequent rain or cloudy weather, choose plants that thrive in these conditions.
Trim back crowded plants. Plants need proper air circulation, and overcrowded ones are more susceptible to powdery mildew. Trim excess shoots from plants that block sunlight from reaching others, and remove weak or wilting plants every two weeks.
- If healthy plants seem to be competing for nutrients, consider replanting them in larger pots or garden beds to provide the necessary air and sunlight they need.
Avoid watering from above. Moisture that accumulates on the leaves can encourage the growth of powdery mildew. Water the base of the plants and allow the water to soak into the soil before watering again. Avoid watering outdoor plants on rainy days to prevent overwatering.
Advice
- Older leaves are usually the first to be affected and may turn yellow and brittle when infected with powdery mildew.
Things You Will Need
- Spray bottle
- Clean cloth
- Baking soda or potassium bicarbonate
- Vegetable oil
- Dish soap
- Vinegar
- Neem oil
- Milk
- Garlic
- Water
