Primitive rock powder, also known as stone powder or rock dust, is an important soil additive. It enriches the soil with many important trace elements. We will explain to you how primary rock powder can also be used against mildew.
How does primary rock dust work against mildew?
Primitive rock flourhas a preventive effect against powdery mildew and downy mildew. The effect is based on the high proportion of silica. These silicon compounds strengthen the cell walls and thereby protect all parts of the plant from the penetration of pathogens such as mildew.
Which primary rock powder is used against mildew?
You should only use primary rock flourwith a high proportion of silica against mildew. The different stone powders vary, among other things, in their silica content between 40 and 70%. Common stone powders consist of bas alt, diabase, zeolite or lava earth. Diabase is recommended against mildew because the alkali silicates it contains are water-soluble. This means that they can be absorbed very well by the plants. Bas alt contains little silica. In the case of zeolites and lava earth, the silica contained hardly dissolves in water.
How do I use primary rock powder against mildew?
Finely ground primary rock flour based on diabase canprevent mildew be sprinkled on the beds around the plants. The amount should be approximately 200 grams per square meter. If the plants are already infected, it makes sense to use it directly on the leaves. Use a powder sprayer to spread the powder on the leaves. Alternatively, you can also boil diabase-based primary rock powder in water and spray the plants with this broth.
What do I have to consider when using primary rock powder?
Stone powders such as diabase and bas alt areslightly to strongly alkaline Many plants love slightly acidic soil, others such as blueberries and hydrangeas require even lower pH values. If you use alkaline primary rock powder, you can damage these plants. That's why stone powder is only suitable for plants that love slightly alkaline soil. These include, for example, yarrow, sage, rosemary and chard.
Tip
Field horsetail brew as a replacement for rock flour
Just like rock dust, field horsetail contains silica. You can remove these from the plants by cooking them for a longer period of time. To make a field horsetail decoction, scald 200 grams of dried field horsetail with one liter of water. Cook the broth for at least 30 minutes. After cooling, you can strain the brew and use it as irrigation water or spray.
