Your roses have a white, mealy coating. If it is easy to wipe off with your hand, it is usually powdery mildew. This fungus causes severe damage to your majestic roses. The flower is often also affected.
Can I fight powdery mildew on roses with vinegar?
Vinegar can help against powdery mildew on roses due to its low pH value of three. Mildew fungi require a neutral pH and cannot exist in acidic conditions. To avoid damaging the plants, you should pay close attention to the application.
How do I use vinegar for mildew on roses?
Vinegar may beonly diluted used on plants. The acidic pH value of the home remedy would not only harm the mildew fungi, but also the plants. As acetic acid you can use household vinegar made from brandy or apple cider vinegar. Eight grams of vinegar per liter of water is ideal for a spray solution. Do not use this mixture in sunlight and heat. This increases the effect of vinegar and thereby burns the leaves of the roses.
What do I have to consider when using vinegar on roses?
When using vinegar in the garden, you should alwaysExercise caution Vinegar as a pesticide is generally prohibited on paved surfaces. Even though the roots of most plants only absorb small amounts of vinegar, the soil quickly becomes acidic after multiple treatments. This also changes the mineral balance. Roses tolerate a slightly acidic soil, with pH values of 7 to 5.5. If treated multiple times, it is helpful to cover the soil around the roses before spraying.
Tip
Alternatives to acetic acid
Other acids are often recommended as home remedies against powdery mildew. Keep in mind that citric acid has a lower pH than household vinegar and lactic acid is only at pH 2.44. Lactic acid should therefore only be used in the form of whole milk.
