Extracting water from discrete xylem and soil samples and continuous (long-term) monitoring of water vapor across the soil-plant-atmosphere continuum remains challenging and under a large debate. Here, we present a detailed one-year study in the Fort Worth Botanic Garden (north-central Texas) to evaluate the analytical robustness of the centrifugation extraction method and understand water sourcing from three common urban tree species (Elderberry, Sambucus canadensis; Cherry Laurel, Prunus caroliniana; and Boxelder Maple, Acer negundo). Xylem (N=110) isotope ratios (δ ¹⁸O and δ ²H) are compared to local precipitation (N=498), throughfall (N=33), and soil water (N=105) at different depths (0-38 cm). Complementary soil water samples were obtained from cup suction lysimeters (N=42) (0-38 cm). Soil and xylem water extraction volumes ranged from 100 µL to 7.5 mL in plant samples and from 100 µL to 10.5 mL in soil samples. Extraction success rates were 68.8% and 75.2% for xylem and soil samples, respectively. The minimum sample total water content for effective extractions was determined as 10.6% (soil) and 17.8% (xylem). Xylem mean narrowband and broadband (proxy for organic contamination) were 0.23±0.40 (-) and 1.00±0.01 (-), respectively. These values agree with mean narrowband and broadband metrics from throughfall and soils, which highlight the non-invasive nature of centrifugated extractions. Annual mean soil δ ¹⁸O compositions (-3.6±1.7‰) corresponded with the throughfall input (-3.6±2.4‰). Xylem δ ¹⁸O compositions exhibited a strong temporal enrichment trend at the end of the winter, summer, and fall seasons. Mean spring xylem δ ¹⁸O (-2.85‰) was less variable and close to soil mean compositions (-2.82‰). For this season, Bayesian mixing analysis showed source water contributions from distinct soil depths: 0 cm to 12.7 cm for Boxelder Maple, 12.7 cm to 25.4 cm for Cherry Laurel, and 12.7 cm to 38.1 cm for Elderberry. Our results offer a standardized and effective protocol for centrifugation extractions and reveal plant water uptake preferences in a highly altered urban green space during an unprecedented warm year.