<p>Soil quality estimation is the biggest concern in the agricultural field for better yield. There are several soil quality indicators among which soil moisture content (SMC) is crucial, significantly influencing soil dielectric properties. In this article, a dual-port square patch sensor with a Defected Ground Structure is designed to investigate the effects of soil texture on dielectric properties under varying moisture levels. The sensor features an electric field distribution of approximately ~ 10⁵&#xa0;V/m and surface current density, ensuring effective interaction with soil samples. A prototype was fabricated, and a dedicated measurement setup is established to determine the relative permittivity of soils with moisture contents ranging from 5% to 30%. The reflection response (S₁₁) analysis is conducted on three soil textures: sandy soil, sandy loam, and clay loam, to explore distinct moisture-dependent dielectric responses. A comparison of actual and predicted moisture contents revealed a strong correlation between sensor readings and calculated&#xa0;SMC. A third-order polynomial fit applied to the data achieved a high coefficient of determination (R²) 0.972, highlighting the sensor's precision in estimating SMC based on its changing resonance characteristics. These findings demonstrate that the proposed sensor provides a novel and reliable approach for soil moisture&#xa0;monitoring, with significant implications for precision agriculture and environmental management.</p>