Bottom 水 — full water radical sitting at the base, picturing a central current with flanking drops. Carries the semantic load: 浆 is a thick liquid, a slurry, the watery-but-viscous stuff like soy milk 豆浆 or paper pulp 纸浆. The radical anchors 浆 in the water family.
Top-left 丬 — half of a split-wood plank, the left half of an ancient 爿 'bedframe' graph. Together with 夕 it supplies the 將 jiāng phonetic frame (same right-side bits as 将, 酱, 桨). Anchors the sound jiāng of 浆 through that phonetic series.
Top-right 夕 — a half-moon rising at dusk, here functioning as the right half of the 將 phonetic frame in this simplified form (the traditional 漿 had 醬-style ⿱將 on top). Together with 丬 above-left it locks in the jiāng reading; it does not contribute the evening meaning.
