Small farmers and gardeners in acid rain-affected regions are facing progressive yet sustained soil acidification, which lowers the productivity of crops, compromises plant growth, and raises the cost of fertilizers. Acid rain, induced by atmospheric contaminants like sulfur dioxide and nitrogen oxides, decrease the soil pH over time, often below the critical threshold of 5.5 for most crops. The people who are affected, like home gardeners and small farmers, usually do not have inexpensive, simple-to-use equipment to test for soil pH in real time. That is, they only discover issues when they see obvious signs, like yellow leaves, slow growth, or fewer flowers,by which time the damage has already occurred and is more difficult to correct. Mitigating soil acidification due to acid rain is paramount for local livelihoods and global sustainability. This problem has a direct link to United Nations Sustainable Development Goals (SDG) 2 (Zero Hunger), SDG 12 (Responsible Consumption and Production), and SDG 15 (Life on Land) since it compromises food security, lowers agricultural productivity, and destroys ecosystems. For small farmers and gardeners, especially in resource-limited settings, being unable to detect and correct soil acidity in time leads to repeated crop failure, financial strain, and loss of traditional farming practices.