The application of fermented apple juice, diluted with water, as a soil amendment or foliar spray, is a practice employed by some gardeners. It introduces acetic acid and other compounds that can influence the soil pH and potentially affect plant health. An example is using a solution of this substance to deter certain fungal diseases or to improve nutrient uptake in acid-loving species.
The purported advantages of this horticultural technique include its potential to create a more acidic environment, which certain plant species thrive in, and its reported ability to control fungal pathogens on foliage. Historically, the use of vinegar-based solutions in gardening has been documented, suggesting an understanding of their impact on soil chemistry and pest management. The benefits are often anecdotal, and scientific studies may vary on confirming efficacy.
