Many gardeners do, but the agronomist warns: You may do more harm than good

Many gardeners are turning to social media for advice on how to grow healthier plants, increase yields, and reduce plant diseases. Tips such as watering tomatoes with milk, adding banana peels to planting holes, spraying plants with baking soda, or even using aspirin have become popular online. However, the question remains—how much truth is actually behind these recommendations? Jerneja Jošar, a university-trained agricultural engineer and author of gardening guides, warns that while social media can be a great source of ideas, many tips circulating online are either misleading, overly generalized, or simply incorrect. She emphasizes the need for critical thinking when evaluating online advice. According to her, some users present personal experiences as universal solutions applicable to all plants and conditions. This approach can lead to unintended consequences, especially when following advice without proper scientific backing or expert validation. Jošar suggests that gardeners should always check whether a tip is supported by research, professional agricultural services, or reliable scientific studies before trying it out. One of the most widely shared tips involves watering tomato plants with milk. While Jošar acknowledges that this practice has some basis in science, she notes that its benefits are limited and often exaggerated. Some studies suggest that diluted milk might help control certain fungal diseases, particularly powdery mildew, by altering the surface environment of leaves. However, she clarifies that milk is not effective against most common tomato diseases, especially late blight, which is one of the biggest threats to tomato plants. Additionally, overuse of milk can cause unpleasant odors, encourage the growth of other microorganisms, and even attract pests. For these reasons, she does not recommend it as a regular preventive measure. Another popular recommendation is the use of baking soda on plants, particularly tomatoes, eggplants, and other vegetables. Jošar explains that baking soda has some antifungal properties due to its ability to change the pH level on leaf surfaces, making it slightly more difficult for certain fungi to develop. However, she cautions that the effectiveness of baking soda depends heavily on the correct concentration. Too high a dose can burn the leaves, especially during hot weather. Moreover, baking soda is not a universal solution for all plant diseases. It is important to understand that it provides limited protection rather than complete immunity against pathogens. The addition of banana peels, crushed eggshells, or coffee grounds to planting holes is another commonly recommended practice. Jošar points out that while each of these methods contains some truth, their benefits are often overstated. Banana peels contain potassium, but the nutrients they provide are released slowly, meaning their impact on plant growth is not immediate. Similarly, crushed eggshells contain calcium, but they break down very slowly in the soil. They are sometimes incorrectly presented as an effective way to prevent fruit rot in tomatoes, despite the fact that this issue is usually linked to inconsistent watering rather than a lack of calcium in the soil. Coffee grounds also come with their own set of considerations. While they contain some nutrients and organic matter, excessive amounts can acidify the soil or hinder the growth of certain plants. Jošar advises caution when applying them in large quantities, as the effects can vary depending on the specific plant species and soil type. Gardeners who rely solely on social media for guidance may find themselves implementing practices that do more harm than good. Without proper understanding or scientific support, these methods could lead to poor plant health, reduced yields, or even damage to the garden ecosystem. Experts stress the importance of consulting verified resources and considering local growing conditions before adopting new techniques. As the popularity of online gardening advice continues to rise, it becomes increasingly crucial for individuals to critically assess the information they receive and seek out reliable, evidence-based guidance.