Horsetail spray is a fermented brew of horsetail (Equisetum arvense).
Horsetail spray – a fermented brew of horsetail (Equisetum arvense). Pour 10 liters of water to 1 kilogram of horsetail, add 500 grams of sugar and let it stand for fifteen to twenty days. Stir every day. After a few days, fermentation starts. The sugar speeds up the fermentation process. The bubbles in the liquid are created by fermentation.
Horsetail spray smells quite bad; do not place the bucket near the house. Strain the brew when ready and mist the liquid over plants with aphids and other sucking insects. Don’t forget the undersides of the leaves: many insects hide there. The sugar in the solution enhances the fermentation process, increases the alcohol content, and the unfermented part of the sugar makes the liquid stick to the sprayed plants. It is the alcohol that kills the insects: alcohol is toxic to insects. Because horsetail contains silicon, the slurry leaves a thin layer of silica on the sprayed leaf, protecting it from sucking insects and fungus (including powdery mildew and Rose black spot). Horsetail is toxic to horses.
The weed horsetail is difficult to remove. A lot of hoeing helps and so does fertilizing, because horsetail grows on poor soil. In nutrient-rich soils, horsetail feels less at home.
